Alters a database in any of the following ways: o For single-file and multifile databases, the ALTER DATABASE statement changes the characteristics of the database root file. The ALTER DATABASE statement lets you override certain characteristics specified in the database root file parameters of the CREATE DATABASE statement, such as whether or not a snapshot file is disabled. In addition, ALTER DATABASE lets you control other characteristics that you cannot specify in the CREATE DATABASE database root file parameters, such as whether or not after-image journaling is enabled. o For single-file and multifile databases, the ALTER DATABASE statement changes the storage area parameters. o For multifile databases only, the ALTER DATABASE statement adds, alters, or deletes storage areas.
1 – Environment
You can use the ALTER DATABASE statement: o In interactive SQL o Embedded in host language programs to be precompiled o As part of a procedure in an SQL module o In dynamic SQL as a statement to be dynamically executed
2 – Format
(B)0[m[1;4mALTER[m[1m [1;4mDATABASE[m[1m qwq> [1;4mFILENAME[m[1m <db-attach-spec> qwwqqqqqqqqqqqqqqqqqqqqqwk [m [1m mq> [1;4mPATHNAME[m[1m <path-name> qqqqqqjm> literal-user-auth qjx [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m [1mmqwqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqwqqqqqqqqqqqqqqqqqqqqqq>[m [1m x tq> alter-root-file-params1 qqqqqqqqqqqqqqu x [m [1m x tq> alter-root-file-params2 qqqqqqqqqqqqqqu x [m [1m x tq> alter-root-file-params3 qqqqqqqqqqqqqqu x [m [1m x tq> alter-journal-params qqqqqqqqqqqqqqqqqu x [m [1m x tq> alter-storage-area-params qqqqqqqqqqqqu x [m [1m x tq> add-row-cache-clause qqqqqqqqqqqqqqqqqu x [m [1m x tq> add-journal-clause qqqqqqqqqqqqqqqqqqqu x [m [1m x tq> add-storage-area-clause qqqqqqqqqqqqqqu x [m [1m x tq> alter-row-cache-clause qqqqqqqqqqqqqqqu x [m [1m x tq> alter-journal-clause qqqqqqqqqqqqqqqqqu x [m [1m x tq> alter-storage-area-clause qqqqqqqqqqqqu x [m [1m x mq> drop-clause qqqqqqqqqqqqqqqqqqqqqqqqqqj x [m [1m mqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m [1mdb-attach-spec = [m [1m [m [1mqqwqqqqqqqqqqqqqqqqwq> <file-spec> qqq> [m [1m mq> <node-spec> qj [m [1m [m (B)0[m[1mnode-spec = [m [1m [m [1mqwq> <nodename> qwqqqqqqqqqqqqqqqqqqqwqwq>[m [1m x mq> <access-string> j x [m [1m mqqqqqqqqqqqqqqqqqq :: <qqqqqqqqqqqqqqj [m (B)0[m[1maccess-string = [m [1m [m [1mqwq> " <user-name> <password> " qqwq> [m [1m mq> " <VMS-proxy-user-name> " qqqj [m [1m [m (B)0[m[1mliteral-user-auth = [m [1m [m [1mqqq> [1;4mUSER[m[1m '<username>' qwqqqqqqqqqqqqqqqqqqqqqqqqwqq> [m [1m mq> [1;4mUSING[m[1m '<password>' qj [m [1m [m (B)0[m[1malter-root-file-params1 = [m [1m [m [1mqwq> attach-options qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq>[m [1m tq> [1;4mNUMBER[m[1m OF [1;4mUSERS[m[1m IS qq> <number-users> qqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mNUMBER[m[1m OF [1;4mBUFFERS[m[1m IS qq> <number-buffers> qqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mNUMBER[m[1m OF [1;4mCLUSTER[m[1m [1;4mNODES[m[1m IS q> <number-nodes> qqqk x [m [1mx[m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m [1mx[m [1mx[m [1mmwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqqqqqqqqqqqqqqqqu[m [1mx[m [1mm>[m [1m( qwq>[m [1;4mSINGLE[m [1mqqqwqq> [1;4mINSTANCE[m[1m qq> )[m [1mqqqj[m [1mx[m [1mx[m [1mmq>[m [1;4mMULTIPLE[m[1m qj[m [1mx[m [1m tq> [1;4mNUMBER[m[1m OF [1;4mRECOVERY[m[1m [1;4mBUFFERS[m[1m IS q> <number-buffers> qqqqqqqqqqqu [m [1m tq> [1;4mBUFFER[m[1m SIZE IS <buffer-blocks> [1;4mBLOCKS[m[1m qqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mSNAPSHOT[m[1m IS qw> [1;4mENABLED[m[1m qwqqqqqq>qqqqqqwqwqqqqqqqqqqqqqqqqqqqu [m [1m x x t> [1;4mIMMEDIATE[m[1m qu x x [m [1m x x m> [1;4mDEFERRED[m[1m qqj x x [m [1m x m> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqj x [m [1m tq> [1;4mDICTIONARY[m[1m IS qqqqqqwq> [1;4mREQUIRED[m[1m qqqqqqqwqqqqqqqqqqqqqqqqqqqqu [m [1m x mq> [1;4mNOT[m[1m [1;4mREQUIRED[m[1m qqqj x [m [1m tq> [1;4mDICTIONARY[m[1m IS qqqqqqwq> [1;4mUSED[m[1m qqqqqqqqqqqwqqqqqqqqqqqqqqqqqqqqu [m [1m x mq> [1;4mNOT[m[1m [1;4mUSED[m[1m qqqqqqqj x [m [1m mq> [1;4mADJUSTABLE[m[1m [1;4mLOCK[m[1m [1;4mGRANULARITY[m[1m IS qwq> [1;4mENABLED[m[1m q> alg-options qwj [m [1m mq> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqj [m (B)0[m[1mattach-options = [m [1m [m [1mqw> [1;4mMULTISCHEMA[m[1m IS w> [1;4mON[m[1m qqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq>[m [1m x m> [1;4mOFF[m[1m qqj x [m [1m m> [1;4mOPEN[m[1m IS qw> [1;4mMANUAL[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m m> [1;4mAUTOMATIC[m[1m wqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwj [m [1m m> ( [1;4mWAIT[m[1m <n> q> MINUTES q> [1;4mFOR[m[1m [1;4mCLOSE[m[1m ) j [m [1m [m (B)0[m[1malg-options = [m [1m [m [1mqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqq> [m [1m mq> ( qq> [1;4mCOUNT[m[1m IS <n> qq> ) qqj [m [1m [m (B)0[m[1malter-root-file-params2 = [m [1mqwq> global-buffer-params qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq> [m [1m tq> [1;4mCARDINALITY[m[1m [1;4mCOLLECTION[m[1m IS qqqqqqqqqqqqwqwq> [1;4mENABLED[m[1m qqqqwqqqu[m [1m tq> [1;4mCARRY[m[1m [1;4mOVER[m[1m [1;4mLOCKS[m[1m ARE qqqqqqqqqqqqqqqqqu mq> [1;4mDISABLED[m[1m qqqj [m [1mx[m [1mtq> [1;4mGALAXY[m [1;4mSUPPORT[m[1m IS[m [1mqqqqqqqqqqqqqqqqqqqqu[m [1mx[m [1m tq> [1;4mLOCK[m[1m [1;4mPARTITIONING[m[1m [1;4mIS[m[1m qqqqqqqqqqqqqqqqqu [m [1mx[m [1mtq> [1;4mLOGMINER[m [1;4mSUPPORT[m [1mIS qqqqqqqqqqqqqqqqqqu[m [1mx[m [1m tq> [1;4mMETADATA[m[1m [1;4mCHANGES[m[1m ARE qqqqqqqqqqqqqqqqqu [m [1mx[m [1m tq> [1;4mSTATISTICS[m[1m [1;4mCOLLECTION[m[1m IS qqqqqqqqqqqqqu [m [1mx[m [1m tq> [1;4mWORKLOAD[m[1m [1;4mCOLLECTION[m[1m IS qqqqqqqqqqqqqqqj [m [1mx[m [1mtq> prestarted-transaction-params qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu[m [1m tq> [1;4mLOCK[m[1m [1;4mTIMEOUT[m[1m [1;4mINTERVAL[m[1m IS <number-seconds> SECONDS qqqqqqqqqqu[m [1m tq> [1;4mRESERVE[m[1m <n> wq> [1;4mCACHE[m[1m [1;4mSLOTS[m[1m qqqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqu[m [1m x tq> [1;4mJOURNALS[m[1m qqqqqqqu [m [1mx[m [1m x tq> [1;4mSTORAGE[m[1m [1;4mAREAS[m[1m qqu [m [1mx[m [1mx[m [1mmq> [1;4mSEQUENCES[m[1m qqqqqqj[m [1mx[m [1m tq> [1;4mROW[m[1m [1;4mCACHE[m[1m IS qwq> [1;4mENABLED[m[1m qqwqqwqqqqqqqqqqqqqqqqqqqqqqqwqqqqu[m [1mx[m [1mmq>[m [1;4mDISABLED[m [1mqj[m [1mmq> row-cache-options qj[m [1mx[m [1mtq> [1;4mSET[m [1mqqwqq> [1;4mTRANSACTION[m[1m [1;4mMODES[m[1m qwqq> txn-modes qwqqqq>) qj[m [1mmq>[m [1;4mALTER[m [1mqj[m [1mmqqqqq> , qqqqqqqqqqj[m (B)0[m[1mglobal-buffer-params= [m [1m [m [1mqq> [1;4mGLOBAL[m[1m [1;4mBUFFERS[m[1m ARE qwq> [1;4mENABLED[m[1m qqwqqqqqqqqqqqqqqk [m [1m mq> [1;4mDISABLED[m[1m qj x [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mtqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqqq> [m [1mm> ( qwwq> [1;4mNUMBER[m[1m IS <number-glo-buffers> qqqqww> ) j [m [1m xtq> [1;4mUSER[m[1m [1;4mLIMIT[m[1m IS <max-glo-buffers> qqqux [m [1m xtq> [1;4mPAGE[m[1m [1;4mTRANSFER[m[1m [1;4mVIA[m[1m qqwq> [1;4mDISK[m[1m qqqwqqjx [m [1m xx mq> [1;4mMEMORY[m[1m qj x [m [1mxmq> [1;4mLARGE[m[1m [1;4mMEMORY[m[1m IS qqwqq> [1;4mENABLED[m [1mqqwqqu[m [1mx[m [1mmqq>[m [1;4mDISABLED[m [1mqj[m [1mx[m [1mmqqqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqqj[m [1m [m [1m [m (B)0[m[1mprestarted-transaction-params = [m [1mq> [1;4mPRESTARTED[m[1m [1;4mTRANSACTIONS[m[1m ARE qwwqq>[m [1;4mENABLED[m [1mqwwqqqqqqqqqqqqqqqqqqqqqqqqqqqqww>[m [1m [m [1mxmqq> [1;4mON[m[1m qqqqqjmq>(prestart-trans-options) qjx[m [1mmqwq> [1;4mDISABLED[m[1m qqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m [1m mq> [1;4mOFF[m[1m qqqqqqqj [m (B)0[m[1mprestart-trans-options =[m [1mqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq>[m [1mtq>[m [1;4mWAIT[m[1m <n> [1;4mSECONDS[m [1;4mFOR[m [1;4mTIMEOUT[m [1mqu[m [1mtq>[m [1;4mWAIT[m[1m <n> [1;4mMINUTES[m [1;4mFOR[m [1;4mTIMEOUT[m [1mqu[m [1mmq>[m [1;4mNO[m [1;4mTIMEOUT[m [1mqqqqqqqqqqqqqqqqqqqj[m (B)0[m[1mrow-cache-options = [m [1m [m [1mq> ( qwwq>[m [1;4mCHECKPOINT[m[1m qwq>[m [1;4mALL[m[1m [1;4mROWS[m[1m [1;4mTO[m[1m [1;4mBACKING[m[1m [1;4mFILE[m[1m qqqqqqqqqqqwqwwq> ) qq> [m [1m [m [1mxx[m [1mtq> [1;4mTIMED[m[1m EVERY <n> SECONDS[m [1mqqqqqqqqqqqqu[m [1mxx[m [1m [m [1mxx[m [1mmq>[m [1;4mUPDATED[m[1m [1;4mROWS[m[1m [1;4mTO[m[1m qwq> [1;4mBACKING[m[1m [1;4mFILE[m [1mqwj[m [1mxx[m [1m xx [m [1m mq> [1;4mDATABASE[m[1m qqqqqj[m [1mxx[m [1mxtq> [1;4mLOCATION[m[1m IS qq> <directory-spec> qqqqqqqqqqqqqqqqqqqqqux[m [1mxtq> [1;4mNO[m[1m qqwqq> [1;4mLOCATION[m[1m qqqqqqqqwqqqqqqqqqqqqqqqqqqqqqqqqqqux[m [1mxx[m [1mmqq>[m [1;4mSWEEP[m[1m [1;4mINTERVAL[m[1m qqj[m [1mxx[m [1mxtq>[m [1;4mNUMBER[m[1m OF [1;4mSWEEP[m[1m [1;4mROWS[m[1m IS <n>[m [1mqqqqqqqqqqqqqqqqqqqqqqqqqqux[m [1mxmq>[m [1;4mSWEEP[m[1m [1;4mINTERVAL[m[1m IS <n> SECONDS[m [1mqqqqqqqqqqqqqqqqqqqqqqqqjx[m [1mmqqqqqqqqqqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m (B)0[m[1mtxn-modes = [m [1m [m [1mqwqwqqqqqqqwqwq> [1;4mREAD[m[1m [1;4mONLY[m[1m qqqqqqqqqqqqqqqqqwqq> [m [1m x mq> [1;4mNO[m[1m qj tq> [1;4mREAD[m[1m [1;4mWRITE[m[1m qqqqqqqqqqqqqqqqu [m [1m x tq> [1;4mBATCH[m[1m [1;4mUPDATE[m[1m qqqqqqqqqqqqqqu [m [1m x tq> [1;4mSHARED[m[1m qqqqwqqwqqqqqqqqqqwqu [m [1m x tq> [1;4mPROTECTED[m[1m qu tq> [1;4mREAD[m[1m qqu x [m [1m x mq> [1;4mEXCLUSIVE[m[1m qj mq> [1;4mWRITE[m[1m qj x [m [1m tqqqqqqqqqqqqq> [1;4mALL[m[1m qqqqqqqqqqqqqqqqqqqqqqqu [m [1m mqqqqqqqqqqqqq> [1;4mNONE[m[1m qqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1malter-root-file-params3 = [m [1m [m [1mqw> [1;4mASYNC[m[1m [1;4mBATCH[m[1m [1;4mWRITES[m[1m ARE qwq> [1;4mENABLED[m[1m q> async-bat-wr-options ww>[m [1m x mq> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqqqqqqqqjx [m [1m twqqqqqqqqqqqqwq> [1;4mASYNC[m[1m [1;4mPREFETCH[m[1m IS qqk x [m [1m xm> [1;4mDETECTED[m[1m qj lqqqqqqqqqqqqqqqqqqqj x [m [1m x mqwq> [1;4mENABLED[m[1m qqq> async-prefetch-options wqqqu [m [1m x mq> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqj x [m [1m twqqqqqqwq> [1;4mINCREMENTAL[m[1m [1;4mBACKUP[m[1m [1;4mSCAN[m[1m [1;4mOPTIMIZATION[m[1m qqqqqqqqqqqqqqqu [m [1m xm> [1;4mNO[m[1m qj x [m [1m t> [1;4mRECOVERY[m[1m [1;4mJOURNAL[m[1m q> ( q> ruj-options q> ) qqqqqqqqqqqqqqqqqqqu [m [1m t> [1;4mSECURITY[m[1m [1;4mCHECKING[m[1m IS qqq> security-checking-options qqqqqqqqqu [m [1mt>[m [1;4mSYNONYMS[m[1m ARE [1;4mENABLED[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu[m [1m t> [1;4mSHARED[m[1m [1;4mMEMORY[m[1m IS qqwq> [1;4mSYSTEM[m[1m qqqqqqqqqqqqqqqqqqqwqqqqqqqqqqqu [m [1mx mq> [1;4mPROCESS[m[1m qqwqqqqqqqqqqqqqwqj[m [1m x [m [1mx[m [1mmq> [1;4mRESIDENT[m [1mqj[m [1mx[m [1mm> [1;4mNOTIFY[m[1m IS qwq>[1;4mENABLED[m [1m qqq> notify-options[m [1mqwqqqqqqqqqqqqqqqj[m [1mmq>[1;4mDISABLED[m [1mqqqqqqqqqqqqqqqqqqqqqqj[m (B)0[m[1masynch-bat-wr-options = [m [1m [m [1mqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq> [m [1m m ( wwq> [1;4mCLEAN[m[1m [1;4mBUFFER[m[1m [1;4mCOUNT[m[1m IS <buffer-count> [1;4mBUFFERS[m[1m qqww> ) j [m [1m xmq> [1;4mMAXIMUM[m[1m [1;4mBUFFER[m[1m [1;4mCOUNT[m[1m IS <buffer-count> [1;4mBUFFERS[m[1m jx [m [1m mqqqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1;7ma[m[1msync-prefetch-options = [m [1m [m [1mqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqw>[m [1m mq> ( qwqwq> [1;4mDEPTH[m[1m IS <number-buffers> [1;4mBUFFERS[m[1m qqqqqwqqw> )qj [m [1m x mq> [1;4mTHRESHOLD[m[1m IS <number-buffers> [1;4mBUFFERS[m[1m qj x [m [1m mqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1mruj-options = [m [1m [m [1mqwq> [1;4mLOCATION[m[1m IS qq> <directory-spec> qwqq> [m [1m tq> [1;4mNO[m[1m [1;4mLOCATION[m[1m qqqqqqqqqqqqqqqqqqqqqqu [m [1m mq> [1;4mBUFFER[m[1m [1;4mMEMORY[m[1m IS qwq> [1;4mLOCAL[m[1m qqqqqqu [m [1mmq> [1;4mGLOBAL[m[1m qqqqqj[m (B)0[m[1msecurity-checking-options =[m [1mqwq>[m [1;4mEXTERNAL[m[1m qwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwwq>[m [1mx [m [1mmq>[m [1m( q> [1;4mPERSONA[m [1;4mSUPPORT[m[1m IS qwq>[m [1;4mENABLED[m [1mqqw> ) qjx[m [1mx[m [1mmq>[m [1;4mDISABLED[m [1mqj[m [1mx[m [1mmq> [1;4mINTERNAL[m[1m qwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqj[m [1mmq> ( q> [1;4mACCOUNT[m [1;4mCHECK[m[1m IS qwqqq>[m [1;4mENABLED[m [1mqqw> ) j[m [1mmqqq>[m [1;4mDISABLED[m[1m qj[m (B)0[m[1malter-journal-params = [m [1m [m [1mq> [1;4mJOURNAL[m[1m IS qqqk [m [1mlqqqqqqqqqqqqqqqqj [m [1mmqw> [1;4mENABLED[m[1m wqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwwq> [m [1m x m> ( wqwq> aij-control-options-1 qwqw> ) jx [m [1m x x mq> aij-control-options-2 qj x x [m [1m x mqqqqqqqqqqqqq , <qqqqqqqqqqqqqj x [m [1m m> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1maij-control-options-1 = [m [1m [m [1mqqwq> [1;4mALLOCATION[m[1m IS <n> BLOCKS qqqqqqqqqqqqqqqqqqqqqqqqqqqqwq> [m [1m tq> [1;4mBACKUP[m[1m [1;4mSERVER[m[1m IS w> [1;4mAUTOMATIC[m[1m w> <backup-file-spec>qqu [m [1m x m> [1;4mMANUAL[m[1m qqqj x [m [1m tq> [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m qqq> <backup-file-spec> qqk x [m [1m x lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj x [m [1m x mq> backup-filename-options qqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mNO[m[1m [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m mq> [1;4mEXTENT[m[1m IS <n> BLOCKS qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m (B)0[m[1mbackup-filename-options = [m [1m [m [1mqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq> [m [1m mq> ( qwq> [1;4mNO[m[1m [1;4mEDIT[m[1m [1;4mSTRING[m[1m qqqqqqqqqqqqqqqqqqqqqqwq> ) qj [m [1m mq> [1;4mEDIT[m[1m [1;4mSTRING[m[1m IS qwqwq> [1;4mSEQUENCE[m[1m qqwqwqj [m [1m x tq> [1;4mYEAR[m[1m qqqqqqu x [m [1m x tq> [1;4mMONTH[m[1m qqqqqu x [m [1m x tq> [1;4mDAY[m[1m qqqqqqqu x [m [1m x tq> [1;4mHOUR[m[1m qqqqqqu x [m [1m x tq> [1;4mMINUTE[m[1m qqqqu x [m [1m x tq> [1;4mJULIAN[m[1m qqqqu x [m [1m x tq> [1;4mWEEKDAY[m[1m qqqu x [m [1m x mq> literal qqqj x [m [1m mqqqqqqqqq + <qqqqqj [m [1m [m (B)0[m[1maij-control-options-2 = [m [1m [m [1mqwq> [1;4mFAST[m[1m [1;4mCOMMIT[m[1m IS qw> [1;4mENABLED[m[1m qqq> fc-options qqwqqqqqqqwq> [m [1m x m> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqqj x [m [1m tq> [1;4mLOG[m[1m [1;4mSERVER[m[1m IS qw> [1;4mMANUAL[m[1m qqqqwqqqqqqqqqqqqqqqqqqqqqqqu [m [1m x m> [1;4mAUTOMATIC[m[1m qj x [m [1m tq> [1;4mOVERWRITE[m[1m IS qqw> [1;4mENABLED[m[1m qqwqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m x m> [1;4mDISABLED[m[1m qj x [m [1m mq> [1;4mSHUTDOWN[m[1m [1;4mTIME[m[1m IS <n> MINUTES qqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1mfc-options = [m [1m [m [1m [m [1m [m [1mqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwq>[m [1m mq> ( qww> [1;4mCHECKPOINT[m[1m qwq> [1;4mINTERVAL[m[1m IS <n> BLOCKS qqqqqqwqwqwq> ) qj [m [1m xx tq> [1;4mTIMED[m[1m [1;4mEVERY[m[1m <n> SECONDS qqqqqu x x[m [1m [m [1mxx[m [1m mq> [1;4mEVERY[m [1m<n> [1;4mTRANSACTIONS[m [1mqqqqqqj[m [1mx[m [1mx[m [1m xtwqqqqqqqwq> [1;4mCOMMIT[m[1m [1;4mTO[m[1m [1;4mJOURNAL[m[1m [1;4mOPTIMIZATION[m[1m qqqqqqu x[m [1m [m [1m xxmq> [1;4mNO[m[1m qj [m [1mx[m [1mx[m [1m xmq> [1;4mTRANSACTION[m[1m [1;4mINTERVAL[m[1m IS <number-txns> qqqqqqqqj x[m [1m mqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m [1m [m [1m [m [1m [m (B)0[m[1mnotify-options = [m [1m [m [1mqqwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqq> [m [1m mqq> ( [1;4mALERT[m[1m [1;4mOPERATOR[m[1m qwqq> operator-class qwqq ) qqj [m [1m mqqqqqqqqq + <qqqqqqqqqj [m [1m [m (B)0[m[1moperator-class = [m [1m [m [1mqqqwqqwqqqqqqwqwqq> [1;4mCENTRAL[m[1m qqqqqwqqq>[m [1m x m> [1;4mNO[m[1m qj tqq> [1;4mDISKS[m[1m qqqqqqqu [m [1m x tqq> [1;4mCLUSTER[m[1m qqqqqu [m [1mx[m [1mtqq> [1;4mCONSOLE[m[1m qqqqqu[m [1mx tqq> [1;4mSECURITY[m[1m qqqqu [m [1m x tqq> [1;4mOPER1[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER2[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER3[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER4[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER5[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER6[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER7[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER8[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER9[m[1m qqqqqqqu [m [1m x tqq> [1;4mOPER10[m[1m qqqqqqu [m [1m x tqq> [1;4mOPER11[m[1m qqqqqqu [m [1m x mqq> [1;4mOPER12[m[1m qqqqqqu [m [1m tqqqqqqqqqqqqqq> [1;4mALL[m[1m qqqqqqqqqu [m [1m mqqqqqqqqqqqqqq> [1;4mNONE[m[1m qqqqqqqqj [m (B)0[m[1mextent-params = [m [1m [m [1mqqwq> [1;4mEXTENT[m[1m IS qwq> [1;4mENABLED[m[1m qqqqqqqqqqqqqqqqqqqwwqq> [m [1m x tq> [1;4mDISABLED[m[1m qqqqqqqqqqqqqqqqqqux [m [1m x tq> <extent-pages> qq> PAGES qqux [m [1m x mq> (extension-options) qqqqqqqjx [m [1m mqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1mextension-options = [m [1m [m [1mqqq> [1;4mMINIMUM[m[1m OF <min-pages> PAGES, qqk [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmqq> [1;4mMAXIMUM[m[1m OF <max-pages> PAGES, qqk [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmqq> [1;4mPERCENT[m[1m [1;4mGROWTH[m[1m IS <growth> qqqqqqq> [m [1m [m (B)0[m[1madd-journal-clause = [m [1m [m [1mqqq> [1;4mADD[m[1m [1;4mJOURNAL[m[1m qqqqq> <journal-name> qqqqqqk [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqwqwqqqqqqqqqqqqqqqqqqqqwqwq> [m [1m mq> [1;4mFILENAME[m[1m <journal-file-spec> qj x mq> add-aij-options qj x [m [1m mqqqqqqqqqq <qqqqqqqqqqqqj [m [1m [m (B)0[m[1madd-aij-options = [m [1m [m [1mqwq> [1;4mALLOCATION[m[1m IS qq> <n> q> BLOCKS qqqqqqqqqqqqqqqwqq> [m [1m tq> [1;4mEXTENT[m[1m IS qq> <n> q> BLOCKS qqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m q> <backup-file-spec> qqqk x [m [1m x lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj x [m [1m x mqq> backup-filename-options qqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mSAME[m[1m [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m [1;4mAS[m[1m [1;4mJOURNAL[m[1m qqqqqqqqqqqqqqqu [m [1m mq> [1;4mNO[m[1m [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1madd-storage-area-clause = [m [1m [m [1mqqq> [1;4mADD[m[1m [1;4mSTORAGE[m[1m [1;4mAREA[m[1m <area-name> qqk [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmqwqqqqqqqqqqqqqqqqqqqqqqqqqwqwwq> storage-area-params-1 qwqwq> [m [1m mq> [1;4mFILENAME[m[1m <file-spec> qj xmq> storage-area-params-2 qj x [m [1m mqqqqqqqqqqqqqq <qqqqqqqqqqqqqj [m [1m [m (B)0[m[1mstorage-area-params-1 = [m [1m [m [1mqqwq> [1;4mALLOCATION[m[1m IS qqq> <number-pages> qq> PAGES qqqqqwq>[m [1m tq> [1;4mCACHE[m[1m [1;4mUSING[m[1m <row-cache-name> qqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mNO[m[1m ROW [1;4mCACHE[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> extent-params qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mINTERVAL[m[1m IS qq> <number-data-pages> qqqqqqqqqqqqqu [m [1m tq> [1;4mLOCKING[m[1m IS qqwq> [1;4mROW[m[1m qqwqq> LEVEL qqqqqqqqqqqqqqqu [m [1m x mq> [1;4mPAGE[m[1m qj x [m [1m tq> [1;4mPAGE[m[1m [1;4mFORMAT[m[1m IS wq> [1;4mUNIFORM[m[1m qwqqqqqqqqqqqqqqqqqqqqu [m [1m x mq> [1;4mMIXED[m[1m qqqj x [m [1m mq> [1;4mPAGE[m[1m [1;4mSIZE[m[1m IS qqqq> <page-blocks> qq> BLOCKS qqqqqj [m [1m [m (B)0[m[1mstorage-area-params-2 = [m [1m [m [1mqqwq> [1;4mCHECKSUM[m[1m CALCULATION IS qqqqqqqqqqqwqqwq> [1;4mENABLED[m[1m qqwqwq>[m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mCHECKSUM[m[1m CALCULATION IS qqj mq> [1;4mDISABLED[m[1m qj x [m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mALLOCATION[m[1m IS qq> <snp-pages> qqqq> PAGES qqqu [m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mEXTENT[m[1m IS qwq> <extent-pages> qqqq> PAGES qqwu [m [1m x mq> (extension-options) qqqqqqqqqjx [m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mFILENAME[m[1m qq> <file-spec> qqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mTHRESHOLDS[m[1m ARE ( <val1> wqqqqqqqqqqqqqqqqqqqqqqqw> ) qu [m [1m x m> ,<val2> qwqqqqqqqqqqwj x [m [1m x m> ,<val3> j x [m [1m mq[mqqqqqqqqqqqqqqqqqqqqqqqqqqqqq[1m<qqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1madd-row-cache-clause = [m [1m [m [1m [m [1m [m [1mqqq> [1;4mADD[m[1m [1;4mCACHE[m[1m <row-cache-name> qwqwqqqqqqqqqqqqqqqqqqqqqqwqwq>[m [1m x tq> row-cache-params1 qu x [m [1m x mq> row-cache-params2[m [1mqj x [m [1mmqqqqqqqqqqqqq<qqqqqqqqqqqqj[m (B)0[m[1malter-row-cache-clause = [m [1m [m [1m [m [1m [m [1m [m [1m [m [1mqqq> [1;4mALTER[m[1m [1;4mCACHE[m[1m <row-cache-name> qwqwqqqqqqqqqqqqqqqqqqqqqqwqwq>[m [1m [m [1mx tq> row-cache-params1[m [1mqu x [m [1m [m [1mx mq> row-cache-params2[m [1mqj[m [1mx [m [1mmqqqqqqqqqqqqq<qqqqqqqqqqqqj[m (B)0[m[1mrow-cache-params1 = [m [1m [m [1m [m [1m [m [1mqqwq> [1;4mALLOCATION[m[1m IS <n> qwqqwqqqqqqqqqqqwqqqqqqqqqqqqqqqqwq> [m [1m tq> [1;4mEXTENT[m[1m IS <n> qqqqqj tq> [1;4mBLOCK[m[1m qqu [m [1m x [m [1m x mq> [1;4mBLOCKS[m[1m qj [m [1m x [m [1m tq> [1;4mCACHE[m[1m [1;4mSIZE[m[1m IS <n> qwqqqq> [1;4mROW[m[1m qqwqqqqqqqqqqqqqqqqqqu [m [1m x mqqqq> [1;4mROWS[m[1m qj [m [1m x [m [1m [m [1mtq>[m [1;4mCHECKPOINT[m[1m qw>[m [1;4mUPDATED[m[1m [1;4mROWS[m[1m TO qw> [1;4mBACKING[m[1m [1;4mFILE[m [1mqwqu[m [1m [m [1mx[m [1mx[m [1mm>[m [1;4mDATABASE[m [1mqqqqqu[m [1mx[m [1m [m [1mx[m [1mm>[m [1;4mALL[m[1m [1;4mROWS[m[1m TO [1;4mBACKING[m[1m [1;4mFILE[m[1m qqqqqqqqqj[m [1mx[m [1m tq> [1;4mLARGE[m[1m [1;4mMEMORY[m[1m IS qqqqwqwq> [1;4mENABLED[m[1m qqwqqqqqqqqqqqqqqu[m [1m [m [1m tq> [1;4mROW[m[1m [1;4mREPLACEMENT[m[1m IS qj mq> [1;4mDISABLED[m[1m qj[m [1m x[m [1m [m [1m tq> [1;4mLOCATION[m[1m IS qq> <directory-spec> qqqqqqqqqqqqqqqqqqu[m [1m [m [1m mq> [1;4mNO[m[1m [1;4mLOCATION[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m [1m [m [1m [m [1m [m (B)0[m[1mrow-cache-params2 = [m [1m [m [1mqqwq> [1;4mNUMBER[m[1m [1;4mOF[m[1m qwq> [1;4mRESERVED[m [1mqwq>[m [1;4mROWS[m[1m IS <n> qqqqqqqqqqqqqqwq>[m [1mx[m [1mmq> [1;4mSWEEP[m[1m qqqqj[m [1mx[m [1m tq> [1;4mROW[m[1m [1;4mLENGTH[m[1m IS <n> qwqqqqqqqqqqqqqwqqqqqqqqqqqqqqqqqqqqqu [m [1m x tqqqq> [1;4mBYTE[m[1m qqu [m [1m [m [1m x [m [1m x mqqqq> [1;4mBYTES[m[1m qj [m [1m [m [1m x [m [1mx[m [1mx[m [1mtq> [1;4mROW[m[1m [1;4mSNAPSHOT[m[1m IS qqwq> [1;4mENABLED[m[1m rs-opt qwqqqqqqqqqqqqqqqu[m [1mx [m [1mmq> [1;4mDISABLED[m[1m qqqqqqqqj[m [1mx[m [1mx[m [1mx[m [1m tq> [1;4mSHARED[m[1m [1;4mMEMORY[m[1m IS qqwqqqq> [1;4mSYSTEM[m[1m qqqqqqqqqqqqqqqqqqqwqqu [m [1m x mqqqq> [1;4mPROCESS[m[1m qqwqqqqqqqqqqqqqwqj[m [1m x [m [1mx[m [1mx[m [1mx[m [1mx[m [1mx[m [1mmq> [1;4mRESIDENT[m[1m qj[m [1mx[m [1mx[m [1mx[m [1mmq> [1;4mWINDOW[m[1m [1;4mCOUNT[m[1m IS <n> qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj[m (B)0[m[1mrs-opt = [m qq[1mwqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqqq>[m [1mmq> ([1;4mCACHE[m[1m [1;4mSIZE[m[1m IS <n> [1;4mROWS[m[1m) qqqj[m (B)0[m[1malter-journal-clause = [m [1m [m [1mqqq> [1;4mALTER[m[1m [1;4mJOURNAL[m[1m qqqwq> <journal-name> qwk [m [1m mq> [1;4mRDB$JOURNAL[m[1m qqqqjx [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmwq> alter-aij-options qqwqqqqqqqqqqqqqqqqqqq> [m [1m mqqqqqqqqqq<qqqqqqqqqqqqj [m [1m [m (B)0[m[1malter-aij-options = [m [1m [m [1mqwq> [1;4mJOURNAL[m[1m IS qq> [1;4mUNSUPPRESSED[m[1m qqqqqqqqqqqqqqqqqqwqqq> [m [1m tq> [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m qqqqq> <backup-file-spec> qk x [m [1m x lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj x [m [1m x mq> backup-filename-options qqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mSAME[m[1m [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m [1;4mAS[m[1m [1;4mJOURNAL[m[1mqqqqqqqqqqqqqqqu [m [1m mq> [1;4mNO[m[1m [1;4mBACKUP[m[1m [1;4mFILENAME[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1m [m (B)0[m[1malter-storage-area-clause = [m [1m [m [1mqqq> [1;4mALTER[m[1m [1;4mSTORAGE[m[1m [1;4mAREA[m[1m <area-name> qk [m [1mlqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj [m [1mmwqqq> alter-storage-area-params qqqqqqqqqqqqqqqwqq> [m [1m mqqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqj [m (B)0[m[1malter-storage-area-params = [m [1m [m [1mqwq> [1;4mALLOCATION[m[1m IS qq> <number-pages> qq> PAGES qqqqqqqqqqwq>[m [1m tq> extent-params qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mCACHE[m[1m [1;4mUSING[m[1m <row-cache-name> qqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mNO[m[1m ROW [1;4mCACHE[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mLOCKING[m[1m IS qwq> [1;4mROW[m[1m qwq> LEVEL qqqqqqqqqqqqqqqqqqqqqu [m [1m x mq> [1;4mPAGE[m[1m qj x [m [1m tq> [1;4mREAD[m[1m [1;4mWRITE[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mREAD[m[1m [1;4mONLY[m[1m qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu [m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mALLOCATION[m[1m IS qq> <snp-pages> qq> PAGES qqqqu [m [1m tq> [1;4mSNAPSHOT[m[1m [1;4mEXTENT[m[1m IS wq> <extent-pages> qq> PAGES qqqwqu [m [1m x mq> (extension-options) qqqqqqqqj x [m [1m tq> [1;4mCHECKSUM[m[1m CALCULATION IS qqqqqqqqqqwqqwq> [1;4mENABLED[m[1m qqwqj [m [1m mq> [1;4mSNAPSHOT[m[1m [1;4mCHECKSUM[m[1m CALCULATION IS qj mq> [1;4mDISABLED[m[1m qj [m [1m [m (B)0[m[1mdrop-clause = [m [1m [m [1mqqwq> [1;4mDROP[m[1m [1;4mCACHE[m[1m <row-cache-name> qqqwqwqqqqqqqqqqqqqwqwq>[m [1m tq> [1;4mDROP[m[1m [1;4mSTORAGE[m[1m [1;4mAREA[m[1m <area-name> qj tq> [1;4mCASCADE[m[1m qqu x [m [1m x mq> [1;4mRESTRICT[m[1m qj x [m [1m mq> [1;4mDROP[m[1m [1;4mJOURNAL[m[1m <journal-name> qqqqqqqqqqqqqqqqqqqqqj [m [1m [m
3 – Arguments
3.1 – ADD CACHE row-cache-name
Adds a new row cache. For information regarding the row-cache- params-1 and row-cache-params-2, see the descriptions under the CREATE CACHE clause.
3.2 – ADD_JOURNAL
Creates a new journal file.
3.3 – ADD_STORAGE_AREA
Specifies the name and file specification for a storage area you want to add to the database. You can use the ADD STORAGE AREA clause only on multifile databases. The storage area name cannot be the same as any other storage area name in the database. The ADD STORAGE AREA clause creates two files: a storage area file with an .rda file extension and a snapshot file with an .snp file extension. If you omit the FILENAME argument, the file specification uses the following defaults: o Device-the current device for the process o Directory-the current directory for the process o File name-the name specified for the storage area The file specification is used for the storage area and snapshot files that comprise the storage area (unless you use the SNAPSHOT FILENAME argument to specify a different file for the snapshot file, which you can only specify with a multifile database). Because the ADD STORAGE AREA clause creates two files with different file extensions, do not specify a file extension with the file specification. If you use the ALTER DATABASE statement to add a storage area, the change is journaled, however, you should back up your database before making such a change.
3.4 – ADJUSTABLE_LOCK_GRANULARITY
Syntax options: ADJUSTABLE LOCK GRANULARITY IS ENABLED | ADJUSTABLE LOCK GRANULARITY IS DISABLED Enables or disables whether or not the database system automatically maintains as few locks as possible on database resources. The default, ENABLED, results in fewer locks against the database. However, if contention for database resources is high, the automatic adjustment of locks can become a CPU drain. You can trade more restrictive locking for less CPU usage in such databases by disabling adjustable lock granularity.
3.5 – ALERT_OPERATOR
Specifies which operator will be notified of the occurrence of a database system event. You can specify the following operator classes: Operator Class Meaning ALL The ALL operator class broadcasts a message to all terminals that are enabled as operators and that are attached to the system or cluster. These terminals must be turned on and have broadcast- message reception enabled. NONE The NONE operator class inhibits the display of messages to the entire system or cluster. [NO] CENTRAL The CENTRAL operator class broadcasts messages sent to the central system operator. The NO CENTRAL operator class inhibits the display of messages sent to the central system operator. [NO] DISKS The DISKS operator class broadcasts messages pertaining to mounting and dismounting disk volumes. The NO DISKS operator class inhibits the display of messages pertaining to mounting and dismounting disk volumes. [NO] CLUSTER The CLUSTER operator class broadcasts messages from the connection manager pertaining to cluster state changes. The NO CLUSTER operator class inhibits the display of messages from the connection manager pertaining to cluster state changes. [NO] CONSOLE The CONSOLE class broadcasts messages to the Oracle Enterprise Manager (OEM). NO CONSOLE inhibits broadcast to OEM. [NO] The SECURITY operator class displays messages SECURITY pertaining to security events. The NO SECURITY operator class inhibits the display of messages pertaining to security events. [NO] OPER1 The OPER1 through OPER12 operator classes display through [NO] messages to operators identified as OPER1 through OPER12 OPER12. The NO OPER1 through NO OPER12 operator classes inhibit messages from being sent to the specified operator.
3.6 – ALLOCATION blocks for aij
Syntax option: ALLOCATION IS n BLOCKS Specifies the number of blocks allocated for the .aij file. The default and minimum is 512 blocks. Even if you specify a value less than 512 blocks, the .aij file is allocated 512 blocks. For information on determining the allocation value, see the Oracle Rdb Guide to Database Design and Definition.
3.7 – ALLOCATION IS n PAGES
Specifies the number of database pages allocated to the storage area. The initial allocation never changes and is used for the hash algorithm. The new allocation becomes the current allocation. If you execute the RMU Dump/Header command, you see the initial and the current allocation. SQL automatically extends the allocation to handle the storage requirements. Pages are allocated in groups of three (known as a clump). An ALLOCATION of 25 pages actually provides for 27 pages of data and subsequent expansion. The default is 700 pages. The altered area is extended if the specified value exceeds the current area allocation. Otherwise the specified value is ignored.
3.8 – ALTER_CACHE
Alters an existing row cache. For more information, see the following arguments: o ALLOCATION_blocks_for_rdc o CACHE_SIZE_IS_n_ROWS o EXTENT_blocks_for_rdc o LARGE_MEMORY o LOCATION o NO_LOCATION o NUMBER_OF_RESERVED_ROWS o SHARED_MEMORY o ROW_REPLACEMENT o ROW_LENGTH o WINDOW_COUNT
3.9 – ALTER_JOURNAL
Alters existing journal files. RDB$JOURNAL is the default journal name if no name is specified.
3.10 – alter-root-file-params
Parameters that control the characteristics of the database root file associated with the database or that control the characteristics that apply to the entire database. You can specify these parameters for either single-file or multifile databases except as noted in the individual parameter descriptions. For more information about database parameters and details about how they affect performance, see the Oracle Rdb7 Guide to Database Performance and Tuning. The ALTER DATABASE statement does not let you change all database root file parameters that you can specify in the CREATE DATABASE statement. You must use the EXPORT and IMPORT statements to change a number of storage area parameters. For more information on changing storage area parameters, see the IMPORT statement.
3.11 – alter-storage-area-params
Parameters that change the characteristics of database storage area files. You can specify the same storage area parameters for either single-file or multifile databases, but the effect of the clauses in this part of an ALTER DATABASE statement differs. o For single-file databases, the storage area parameters change the characteristics for the single storage area in the database. o For multifile databases, the storage area parameters change the characteristics of the RDB$SYSTEM storage area. You can also change some of the characteristics of the RDB$SYSTEM storage area using the ALTER STORAGE AREA clause. However, you can only change the read-only and read/write parameters in this part of the ALTER DATABASE statement. See the ALTER_STORAGE_AREA topic in this Arguments list for more information about the RDB$SYSTEM characteristics that you are allowed to alter. The ALTER DATABASE statement does not let you change all storage area parameters you can specify in the CREATE DATABASE statement. You must use the EXPORT and IMPORT statements to change the following database root file parameters: o INTERVAL o PAGE FORMAT o PAGE SIZE o SNAPSHOT FILENAME o THRESHOLDS
3.12 – ALTER_STORAGE_AREA
Specifies the name of an existing storage area in the database that you want to alter. You can use the ALTER STORAGE AREA clause only on multifile databases. You can specify RDB$SYSTEM for the area-name if you are altering the following clauses: o ALLOCATION IS number-pages PAGES o extent-params o CACHE USING row-cache-name o NO ROW CACHE o SNAPSHOT ALLOCATION IS snp-pages PAGES o SHAPSHOT EXTENT o CHECKSUM CALCULTION o SNAPSHOT CHECKSUM CALCULATION Oracle Rdb generates an error if you specify RDB$SYSTEM or the DEFAULT storage area as the area-name when altering the following clauses: o LOCKING IS PAGE LEVEL o READ WRITE o READ ONLY If you want to change the read-only and read/write parameters of the RDB$SYSTEM storage area using the ALTER DATABASE statement, you must specify these parameters outside of the ALTER STORAGE AREA clause.
3.13 – ALTER_TRANSACTION_MODES
Enables or disables the modes specified leaving the previously defined or default modes enabled. This is an offline operation and requires exclusive database access. If the current transaction modes are SHARED and READ ONLY and you want to add the EXCLUSIVE mode, use the following statement: SQL> ALTER DATABASE FILENAME mf_personnel cont> ALTER TRANSACTION MODES (EXCLUSIVE);
3.14 – ASYNC_BATCH_WRITES
Syntax options: ASYNC BATCH WRITES ARE ENABLED | ASYNC BATCH WRITES ARE DISABLED Specifies whether asynchronous batch-writes are enabled or disabled. Asynchronous batch-writes allow a process to write batches of modified data pages to disk asynchronously (the process does not stall while waiting for the batch-write operation to complete). Asynchronous batch-writes improve the performance of update applications without the loss of data integrity. By default, batch-writes are enabled. For more information about when to use asynchronous batch-writes, see the Oracle Rdb7 Guide to Database Performance and Tuning. You can enable asynchronous batch-writes by defining the logical name RDM$BIND_ABW_ENABLED.
3.15 – ASYNC_PREFETCH
Syntax options: ASYNC PREFETCH IS ENABLED | ASYNC PREFETCH IS DISABLED Specifies whether or not Oracle Rdb reduces the amount of time that a process waits for pages to be read from disk by fetching pages before a process actually requests the pages. Prefetch can significantly improve performance, but it may cause excessive resource usage if it is used inappropriately. Asynchronous prefetch is enabled by default. For more information about asynchronous prefetch, see the Oracle Rdb7 Guide to Database Performance and Tuning. You can enable asynchronous prefetch by defining the logical name RDM$BIND_APF_ENABLED.
3.16 – BACKUP_FILENAME
Syntax option: BACKUP FILENAME backup-file-spec Specifies the default file specification to be used by the backup server. During execution, the backup server and the RMU Backup After_ Journal command use this file specification as the name of the backup file. You can override this value by specifying a file name for the journal file using the RMU Backup After_Journal command.
3.17 – backup-filename-options
Specifies whether or not the backup file name includes an edit string. When the EDIT STRING clause is used, the specified backup file name is edited by appending any or all of the edit string options listed in the following table. Edit String Option Meaning SEQUENCE The journal sequence number of the first journal file in the backup operation. YEAR The current year expressed as a 4-digit integer. MONTH The current month expressed as a 2-digit integer (01-12). DAY The current day of the month expressed as a 2- digit integer (00-31). HOUR The current hour of the day expressed as a 2-digit integer (00-23). MINUTE The current minute of the hour expressed as a 2-digit integer (00-59). JULIAN The current day of the year expressed as a 3-digit integer (001-366). WEEKDAY The current day of the week expressed as a 1-digit integer (1-7) where 1 is Sunday and 7 is Saturday. literal Any string literal. This string literal is copied to the file specification. See Quoted Character String for more information about string literals. Use a plus sign (+) between multiple edit string options. The edit string should be 32 characters or less in length. The default is NO EDIT STRING which means the BACKUP FILENAME supplied is all that is used to name the backup file.
3.18 – BACKUP_SERVER
Syntax options: BACKUP SERVER IS AUTOMATIC backup-file-spec | BACKUP SERVER IS MANUAL backup-file-spec Specifies whether the backup server runs automatically or manually. If BACKUP SERVER IS MANUAL is specified, you must execute the RMU Backup After_Journal command manually. If BACKUP SERVER IS AUTOMATIC is specified, a special backup server runs when a journal file in the set is full and causes a switch over to another journal file. The default is MANUAL.
3.19 – BUFFER_SIZE
Syntax option: BUFFER SIZE IS buffer-blocks BLOCKS Specifies the number of blocks Oracle Rdb allocates per buffer. You need to specify an unsigned integer greater than zero. The default buffer size is 3 times the PAGE SIZE value (6 blocks for the default PAGE SIZE of 2). The buffer size is a global parameter and the number of blocks per page (or buffer) is constrained to 64 blocks per page. The page size can vary by storage area for multifile databases, and the page size should be determined by the sizes of the records that will be stored in each storage area. When choosing the number of blocks per buffer, choose a number so that a round number of pages fits in the buffer. In other words, the buffer size is wholly divisible by all page sizes for all storage areas in your multifile database. For example, if you have three storage areas with page sizes of 2, 3, and 4 blocks each respectively, choosing a buffer size of 12 blocks ensures optimal buffer utilization. In contrast, choosing a buffer size of 8 wastes 2 blocks per buffer for the storage area with a page size of 3 pages. Oracle Rdb reads as many pages as fit into the buffer; in this instance it reads two 3-block pages into the buffer, leaving 2 wasted blocks. The altered buffer size must allow for existing page sizes. You cannot specify a buffer size smaller than the largest existing page size.
3.20 – CACHE_USING
Specifies that the named row cache is the default physical row cache for all storage areas in the database. All rows stored in each storage area are cached, regardless of whether they consist of table data, segemented string data, or are special rows such as index nodes. You must either add the specified cache before completing the ALTER DATABASE statement, or it must already exist. Alter the database and storage area to asign a new physical area row cache that overrides the database default physical area row cache. Only one physical area row cache is allowed for each storage area. You can have multiple row caches that contain rows for a single storage area by defining logical area row caches, where the row cache name matches the name of a table or index. If you do not specify the CACHE USING clause or the NO ROW CACHE clause, then the NO ROW CACHE clause is the default.
3.21 – CARDINALITY_COLLECTION
Syntax options: CARDINALITY COLLECTION IS ENABLED | CARDINALITY COLLECTION IS DISABLED Specifies whether or not the optimizer records cardinality updates in the system tables. When enabled, the optimizer collects cardinalities for tables and indexes as rows are inserted or deleted from tables. The update of the cardinalities is performed at commit time, if sufficient changes have accumulated, or at disconnect time. In high update environments, it may be more convenient to disable cardinality updates. If you disable this feature, you should manually maintain the cardinalities using the RMU Collect Optimizer_Statistics command so that the optimizer is given the most accurate values for estimation purposes. Cardinality collection is enabled by default.
3.22 – CARRY_OVER_LOCKS
Syntax options: CARRY OVER LOCKS ARE ENABLED | CARRY OVER LOCKS ARE DISABLED Enables or disables carry-over lock optimization. Carry-over lock optimization holds logical area locks (table and index) across transactions. Carry-over locks are enabled by default and are available as an online database modification. For more information on carry-over lock optimization, see the CREATE DATABASEstatement.
3.23 – CHECKPOINT EVERY n TRANSACTIONS
A FAST COMMIT option which allows the checkpoint to be generated after a set number of transactions. See the following example. SQL> alter database cont> filename db$:scratch cont> cont> journal is enabled cont> (fast commit is enabled cont> (checkpoint every 20 transactions, cont> checkpoint timed every 20 seconds cont> ) cont> ) cont> add journal rdb$journal cont> filename db$:scratch_aij cont> ; %RDMS-W-DOFULLBCK, full database backup should be done to ensure future recovery
3.24 – CHECKPOINT_INTERVAL
Syntax option: CHECKPOINT INTERVAL IS n BLOCKS You can limit how many transactions the database recovery process (DBR) must redo by setting a checkpoint interval. Setting a checkpoint interval instructs Oracle Rdb to periodically write modified pages to disk. This shortens recovery time. The value you assign to the checkpoint interval specifies the number of blocks the .aij file is allowed to increase to before updated pages are transferred. For example, if you set the checkpoint interval value equal to 100, all processes transfer updated pages to the disk when 100 blocks were written to the .aij file since the last checkpoint. Thus all processes contribute to .aij growth. If no checkpoint interval is established and a process completes 1000 transactions but fails during number 1001, the DBR must redo transactions 1 through 1000 and undo number 1001. When a process attaches to the database, it writes a checkpoint record to the .aij file and notes the virtual block number (VBN) of the .aij file at which the checkpoint record is located. If the checkpoint is located at VBN 120 and the checkpoint interval is 100 blocks, the process checkpoints again when VBN 220 is reached. Because all processes contribute to .aij file growth, a process may be able to commit many transactions before checkpointing if update activity by other processes is low. Conversely, if a process' first transaction is long and if update activity by other processes is high, the process may be forced to checkpoint when it commits its first transaction. When the database checkpoint interval value is reached, Oracle Rdb executes the following steps: 1. Writes updated pages to the disk. 2. Writes a checkpoint record to the .aij file. 3. Updates the run-time user process block (RTUPB) for each process to indicate where the checkpoint record is stored in the .aij file. The RTUPB is a data structure in the database root file that maintains information on each process accessing the database. The database recovery process (DBR) uses the RTUPB checkpoint entry to determine where in the .aij file recovery must start.
3.25 – CHECKPOINT TIMED for fast commit
Assigns a value to the checkpoint interval specifying the number of seconds that can pass before updated pages are written. When the specified number of seconds elapsed, Oracle Rdb executes the checkpoint steps. For example, if you specify TIMED EVERY 100 SECONDS, each process checkpoints after at least 100 seconds have passed since its last checkpoint. You can set both a checkpoint based on time and a checkpoint based on .aij file growth; Oracle Rdb performs a checkpoint operation at whichever checkpoint it reaches first. The following statement enables fast commit processing and specifies checkpoint intervals of 512 blocks and 12 seconds: SQL> ALTER DATABASE FILENAME test1 cont> JOURNAL IS ENABLED cont> (FAST COMMIT ENABLED cont> (CHECKPOINT INTERVAL IS 512 BLOCKS, cont> CHECKPOINT TIMED EVERY 12 SECONDS) cont> );
3.26 – Checkpoint Rows
Syntax options: CHECKPOINT UPDATED ROWS TO BACKING FILE CHECKPOINT UPDATED ROWS TO DATABASE CHECKPOINT ALL ROWS TO BACKING FILE Specifies the default source and target during checkpoint operations for all row caches. If ALL ROWS is specified, then the source records written during each checkpoint operation are both the modified and the unmodified rows in a row cache. If UPDATED ROWS is specified, then just the modified rows in a row cache are checkpointed each time. If the target of the checkpoint operation is BACKING FILE, then the RCS process writes the source row cache entries to the backing (.rdc) files. The row cache LOCATION, ALLOCATION, and EXTENT clauses are used to create the backing files. Upon recovery from a node failure, the database recovery process is able to repopulate the row caches in memory from the rows found in the backing files. If the target is DATABASE, then updated row cache entries are written back to the database. The row cache LOCATION, ALLOCATION, and EXTENT clauses are ignored. Upon recovery from a node failure, the database recovery process has no data on the contents of the row cache. Therefore, it does not repopulate the row caches in memory. The CHECKPOINT clause of the CREATE CACHE, ADD CACHE, or ALTER CACHE clause overrides this database-level CHECKPOINT clause.
3.27 – CHECKSUM_CALCULATION
Syntax options: CHECKSUM CALCULATION SNAPSHOT CHECKSUM CALCULATION This option allows you to enable or disable calculations of page checksums when pages are read from or written to the storage area or snapshot files. The default is ENABLED. NOTE Oracle Corporation recommends that you leave checksum calculations enabled, which is the default. With current technology, it is possible that errors may occur that the checksum calculation can detect but that may not be detected by either the hardware, firmware, or software. Unexpected application results and database corruption may occur if corrupt pages exist in memory or on disk but are not detected. Oracle Corporation recommends performing checksum calculations, except in the following specific circumstances: o Your application is stable and has run without errors on the current hardware and software configuration for an extended period of time. o You have reached maximum CPU utilization in your current configuration. Actual CPU utilization by the checksum calculation depends primarily on the size of the database pages in your database. The larger the database page, the more noticeable the CPU usage by the checksum calculation may become. NOTE Oracle Corporation recommends that you carefully evaluate the trade-off between reducing CPU usage by the checksum calculation and the potential for loss of database integrity if checksum calculations are disabled. Oracle Corporation allows you to disable and, subsequently, re-enable checksum calculation without error. However, once checksum calculations have been disabled, corrupt pages may not be detected even if checksum calculations are subsequently re-enabled.
3.28 – CLEAN_BUFFER_COUNT
Syntax option: CLEAN BUFFER COUNT IS buffer-count BUFFERS Specifies the number of buffers to be kept available for immediate reuse. The default is five buffers. The minimum value is one; the maximum value can be as large as the buffer pool size. You can override the number of clean buffers by defining the logical name RDM$BIND_CLEAN_BUF_CNT. For information about how to set the values, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.29 – COMMIT_TO_JOURNAL_OPTIMIZATION
Syntax options: COMMIT TO JOURNAL OPTIMIZATION | NO COMMIT TO JOURNAL OPTIMIZATION If you enable COMMIT TO JOURNAL OPTIMIZATION when you enable fast commit processing, Oracle Rdb does not write commit information to the database root file. This option enhances performance in database environments that are update-intensive. Because of the prerequisites for enabling the journal optimization option, general-use databases or databases that have many read- only transactions may not benefit from this feature. For more information, see the Oracle Rdb7 Guide to Database Performance and Tuning. NOTE If you specify COMMIT TO JOURNAL OPTIMIZATION, you must disable or defer snapshots. If you change snapshots to ENABLED IMMEDIATE, then you must specify NO COMMIT TO JOURNAL OPTIMIZATION.
3.30 – COUNT IS n
Specifies the number of levels on the page lock tree used to manage locks. For example, if you specify COUNT IS 3, the fanout factor is (10, 100, 1000). Oracle Rdb locks a range of 1000 pages and adjusts downward to 100 and then to 10 and then to 1 page when necessary. If the COUNT IS clause is omitted, the default is 3. The value of n can range from 1 through 8.
3.31 – DEPTH buffers option
Syntax option: DEPTH IS number-buffers BUFFERS Specifies the number of buffers to prefetch for a process. The default is one-quarter of the buffer pool, but not more than eight buffers. You can override the number of buffers specified in the CREATE or ALTER DATABASE statements by using the logical name RDM$BIND_APF_DEPTH. You can also specify this option with the DETECTED ASYNC PREFETCH clause.
3.32 – DETECTED_ASYNC_PREFETCH
Syntax options: DETECTED ASYNC PREFETCH IS ENABLED | DETECTED ASYNC PREFETCH IS DISABLED Specifies whether or not Oracle Rdb reduces the amount of time that a process waits for pages to be read from disk. By using heuristics, detected asynchronous prefetch determines if an I/O pattern is sequential in behavior even if sequential I/O is not actually executing at the time. For example, when a LIST OF BYTE VARYING column is fetched, the heuristics detect that the pages being fetched are sequential and asynchronously fetches pages further in the sequence. This avoids wait times when the page is really needed. Detected asynchronous prefetch is enabled by default.
3.33 – DICTIONARY required option
Syntax options: DICTIONARY IS REQUIRED | DICTIONARY IS NOT REQUIRED Specifies whether or not definition statements issued for the database must also be stored in the repository. If you specify the REQUIRED option, any data definition statements issued after an ATTACH or DECLARE ALIAS statement that does not specify the PATHNAME argument fails. If you specify the DICTIONARY argument in an ALTER DATABASE statement, you cannot specify any other database root file or storage area parameters. If you omitted the PATHNAME clause from the database root file parameters in the CREATE DATABASE statement that created the database, SQL generates an error if you specify DICTIONARY IS REQUIRED in an ALTER DATABASE statement for the same database. This is not true if you use the INTEGRATE statement with the CREATE PATHNAME clause to copy database definitions to the repository before specifying the DICTIONARY IS REQUIRED clause in an ALTER DATABASE statement for that database.
3.34 – DICTIONARY used option
Syntax options: DICTIONARY IS USED | DICTIONARY IS NOT USED Specifies whether or not to remove the link between the repository and the database. If you specify the DICTIONARY IS NOT USED clause, the definitions in both the repository and database are still maintained. After removing the links, you can integrate the database to a new repository. The DICTIONARY IS USED clause is the default.
3.35 – DROP_CACHE
Syntax options: DROP CACHE row-cache-name CASCADE | DROP CACHE row-cache-name RESTRICT Deletes the specified row cache from the database. If the mode is RESTRICT, then an exeption is raised if the row cache is assigned to a storage area. If the mode is CASCADE, then the row cache is removed from all referencing storage areas. The default is RESTRICT if no mode is specified.
3.36 – DROP_JOURNAL
Deletes the specified journal file from the database. You can only delete an .aij file that is not current and that has been backed up.
3.37 – DROP_STORAGE_AREA
Syntax options: DROP STORAGE AREA area-name CASCADE | DROP STORAGE AREA area-name RESTRICT Deletes the specified storage area definition and the associated storage area and snapshot files. You can use the DROP STORAGE AREA clause only on multifile databases. If you use the RESTRICT keyword, you cannot delete a storage area if any database object, such as a storage map, refers to the area or if there is data in the storage area. If you use the CASCADE keyword, Oracle Rdb modifies all objects that refer to the storage area so that they no longer refer to it. However, Oracle Rdb does not delete objects if doing so makes the database inconsistent. If you use the ALTER DATABASE statement to delete a storage area, the change is journaled, however, you should back up your database before making such a change.
3.38 – EXTENT blocks for aij
Specifies the number of blocks of each .aij file extent. The default and minimum extent for .aij files is 512 blocks.
3.39 – EXTENT clause
Syntax options: EXTENT ENABLED | EXTENT DISABLED Enables or disables extents. Extents are ENABLED by default and can be changed on line; however, the new extents are not immediately effective on all nodes of a cluster. On the node on which you have changed extents, the new storage area extents are immediately effective for all users. The new storage area extents become effective as the database is attached on each node of the cluster. You can encounter performance problems when creating hashed indexes in storage areas with the mixed page format if the storage area was created specifying the wrong size for the area and if extents are enabled. By disabling extents, this problem can be diagnosed early and corrected to improve performance.
3.40 – EXTENT pages
Syntax options: EXTENT IS extent-pages PAGES | EXTENT IS (extension-options) Changes the number of pages of each storage area file extent. See the description under the SNAPSHOT EXTENT argument.
3.41 – FAST_COMMIT
Syntax options: FAST COMMIT IS ENABLED | FAST COMMIT IS DISABLED By default, Oracle Rdb writes updated database pages to the disk each time a transaction executes the COMMIT statement. If a transaction fails before committing, Oracle Rdb only needs to roll back (undo) the current failed transaction; it never has to redo previous successful transactions. You can change the commit processing method by enabling journal fast commit processing. With journal fast commit enabled, Oracle Rdb keeps updated pages in the buffer pool (in memory) and does not write the pages to the disk when a transaction commits. The updated pages remain in the buffer pool until the process meets a condition specified by the database administrator or applications programmer. At the moment the condition is met (the checkpoint), all the pages the process updated for multiple transactions are written to the disk. You can set a checkpoint for your process when: o A fixed number of transactions are committed or aborted. You set this by specifying CHECKPOINT EVERY n TRANSACTIONS. o A specified time interval elapsed. You set this by specifying the CHECKPOINT TIMED EVERY n SECONDS clause. o The after-image journal (.aij) file increased by a specified number of blocks. You set this by specifying the CHECKPOINT INTERVAL IS n BLOCKS clause. If a transaction fails, Oracle Rdb must undo the current, failed transaction and redo all the committed transactions since the last checkpoint. Redoing updates involves reading the .aij file and reapplying the changes to the relevant data pages. Fast commit processing applies only to data updates: erase, modify, and store operations. Transactions that include data definition statements, such as create logical area or create index operations, force a checkpoint at the end of the transaction. If you do not specify values with the FAST COMMIT clause, the default values are applied. NOTE To enable FAST COMMIT, you must first enable after-image journaling.
3.42 – FILENAME file spec
Identifies the database root file associated with the database. If you specify a repository path name, the path name indirectly specifies the database root file. The ALTER DATABASE statement does not change any definitions in the repository, so there is no difference in the effect of the PATHNAME and FILENAME arguments. If you specify PATHNAME, SQL does not use the repository's fully qualified name. Instead, SQL uses the name stored as the user- supplied name in the repository. In the following example, SQL uses the name TEST as the file name, not DB$DISK:[DBDIR]TEST.RDB. As a result, the database root file must be located in your present working directory or the database name must be a logical name when you use the PATHNAME clause. $ REPOSITORY OPERATOR . . . CDO> show database/full test Definition of database TEST | database uses RDB database TEST | database in file TEST | | fully qualified file DB$DISK:[DBDIR]TEST.RDB; | | user-specified file DB$DISK:[DBDIR]test.rdb If the database referred to in the PATHNAME or FILENAME argument has been attached, the ALTER DATABASE statement will fail with a file access conflict error.
3.43 – FILENAME journal file spec
Specifies the journal file specification with the default file extension .aij.
3.44 – GALAXY_SUPPORT
Syntax options: GALAXY SUPPORT IS ENABLED|GALAXY SUPPORT IS DISABLED Allows global memory to be shared in an OpenVMS Galaxy configuration. Galaxy support is disabled by default. OpenVMS Galaxy is a software architecture for the OpenVMS Alpha operating system that enables multiple instances of OpenVMS to execute cooperatively in a single computer. An instance refers to a copy of the OpenVMS Alpha operating system. As an extension of the existing OpenVMS cluster support within Oracle Rdb, Oracle Rdb provides support for databases opened on multiple instances (or nodes) within a Galaxy system to share data structures in memory. Within an Oracle Rdb Galaxy environment, all instances with an open database share: o Database root objects (for example, TSN blocks and SEQ blocks) o Global buffers (if enabled) o Row caches and Row Cache Server process (RCS) (if enabled)
3.45 – GLOBAL_BUFFERS
Syntax options: GLOBAL BUFFERS ARE ENABLED | GLOBAL BUFFERS ARE DISABLED Specifies whether or not Oracle Rdb maintains one global buffer pool per VMScluster node for each database. By default, Oracle Rdb maintains a local buffer pool for each attach (GLOBAL BUFFERS ARE DISABLED). For more than one attach to use the same page, each must read it from the disk into their local buffer pool. A page in the global buffer pool can be read by more than one attach at the same time, although only one attach reads the page from the disk into the global buffer pool. Global buffers improve performance because the I/O is reduced, and memory is better utilized. NOTE If GALAXY SUPPORT is enabled, then a single global buffer pool is shared by all Galaxy nodes.
3.46 – INCREMENTAL_BACKUP_SCAN_OPTIMIZATION
Syntax options: INCREMENTAL BACKUP SCAN OPTIMIZATION | NO INCREMENTAL BACKUP SCAN OPTIMIZATION Specifies whether Oracle Rdb checks each area's SPAM pages or each database page to find changes during incremental backup. If you specify INCREMENTAL BACKUP SCAN OPTIMIZATION, Oracle Rdb checks each area's SPAM pages and scans the SPAM interval of pages only if the SPAM transaction number (TSN) is higher than the last full backup TSN, which indicates that a page in the SPAM interval has been updated since the last full backup operation. Specify INCREMENTAL BACKUP SCAN OPTIMIZATION if your database has large SPAM intervals or infrequently occurring updates, and you want to increase the speed of incremental backups. If you disable the attribute (using the NO INCREMENTAL BACKUP SCAN OPTIMIZATION clause), you cannot enable it until immediately after the next full backup. If you specify NO INCREMENTAL BACKUP SCAN OPTIMIZATION, Oracle Rdb checks each page to find changes during incremental backup. Specify the NO INCREMENTAL BACKUP SCAN OPTIMIZATION clause if your database has frequently occurring updates, uses bulk-load operations, or does not use incremental backups, or if you want to improve run-time performance. The default is INCREMENTAL BACKUP SCAN OPTIMIZATION.
3.47 – JOURNAL clause for aij
Syntax options: JOURNAL IS ENABLED | JOURNAL IS DISABLED Specifies whether or not journaling is enabled. If journal files already exist, the JOURNAL IS ENABLED clause simply restarts the journaling feature. If no journal files exist when the ALTER DATABASE . . . JOURNAL IS ENABLED statement completes, an exception is raised. For example: SQL> ALTER DATABASE FILENAME sample cont> JOURNAL IS ENABLED; %RDMS-F-NOAIJENB, cannot enable after-image journaling without any AIJ journals Use the ADD JOURNAL clause to create journal files. The ENABLED option can be followed by a list of database journal options. All journal files remain unchanged but become inaccessible when you disable them. You cannot specify database journal options with the DISABLED option.
3.48 – JOURNAL_IS_UNSUPPRESSED
If a journal file becomes inaccessible, it is disabled by the journaling system. It remains in that state until you correct the problem and manually unsuppress that journal file.
3.49 – literal-user-auth
Specifies the user name and password for access to databases, particularly remote database. This literal lets you explicitly provide user name and password information in the ALTER DATABASE statement.
3.50 – LOCATION IS directory-spec
Specifies the name of the default directory to which row cache backing file information is written. The database system generates a file name (row-cache-name.rdc) automatically for each row cache backing file it creates when the RCS process starts up. Specify a device name and directory name enclosed within single quotation marks ('); do not include a file specification. The file name is the row-cache-name specified when creating the row cache. By default, the location is the directory of the database root file. The LOCATION clause of the CREATE CACHE, ADD CACHE, or ALTER CACHE clause overrides this location, which is the default for the database. This clause is ignored if the row cache is defined to checkpoint to the database.
3.51 – LOCK_PARTITIONING
Syntax options: LOCK PARTITIONING IS ENABLED | LOCK PARTITIONING IS DISABLED Specifies whether more than one lock tree is used for the database or all lock trees for a database are mastered by one database resource tree. When partitioned lock trees are enabled for a database, locks for storage areas are separated from the database resource tree and all locks for each storage area are independently mastered on the VMScluster node that has the highest traffic for that resource. OpenVMS determines the node that is using each resource the most and moves the resource hierarchy to that node. You cannot enable lock partitioning for single-file databases. You should not enable lock partitioning for single-node systems, because all lock requests are local on single-node systems. By default, lock partitioning is disabled.
3.52 – LOCK_TIMEOUT_INTERVAL
Syntax option: LOCK TIMEOUT INTERVAL IS number-seconds SECONDS Specifies the number of seconds for processes to wait during a lock conflict before timing out. The number can be between 1 and 65,000 seconds. Specifying 0 is interpreted as no lock timeout interval being set. It is not interpreted as 0 seconds. The lock timeout interval is database-wide; it is used as the default and the upper limit when determining the timeout interval. For example, if the database definer specified LOCK TIMEOUT INTERVAL IS 25 SECONDS in the ALTER DATABASE statement, and a user of that database specified SET TRANSACTION WAIT 30 or changed the logical name RDM$BIND_LOCK_TIMEOUT_INTERVAL to 30, SQL still uses the interval 25. For more information on timeout intervals, see the Oracle Rdb7 Guide to Distributed Transactions.
3.53 – LOCKING level
Syntax options: LOCKING IS ROW LEVEL | LOCKING IS PAGE LEVEL Specifies if locking is at the page or row level. This clause provides an alternative to requesting locks on records. The default is ROW LEVEL. When many records are accessed in the same area and on the same page, the LOCKING IS PAGE LEVEL clause reduces the number of lock operations perfomed to process a transaction; however, this is at the expense of reduced concurrency because these page locks are held until COMMIT/ROLLBACK time. Transactions that benefit most with page-level locking are of short duration and also access several database records on the same page. Use the LOCKING IS ROW LEVEL clause if transactions are long in duration and lock many rows. The LOCKING IS PAGE LEVEL clause causes fewer blocking asynchronous system traps and provides better response time and utilization of system resources. However, there is a higher contention for pages and increased potential for deadlocks and long transactions may use excessive locks. Page-level locking is never applied to RDB$SYSTEM or the DEFAULT storage area, either implicitly or explicitly, because the locking protocol can stall metadata users. You cannot specify page-level locking on single-file databases.
3.54 – LOG_SERVER
Syntax options: LOG SERVER IS MANUAL | LOG SERVER IS AUTOMATIC Specifies if the AIJ log server (ALS) is activated manually or automatically. The default is manual. Multiple-user databases with medium to high update activity can experience after-image journal (.aij) file bottlenecks. To alleviate these bottlenecks, you can specify the LOG SERVER clause to transfer log data to the .aij file either automatically or manually. On a single node with ALS, there is no AIJ locking. If the log server is set to MANUAL, you must execute the RMU Server After_Journal command with the Start qualifier to start the log server. In this case, the database must already be open. If the OPEN IS MANUAL clause was specified, an explicit RMU Open command needs to be executed before the log server is started. If the OPEN IS AUTOMATIC clause was specified, at least one user should be attached to the database before the log server is started. If the log server is set to AUTOMATIC, the log server starts when the database is opened, automatically or manually, and is shut down when the database is closed. For more information on setting log servers, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.55 – LOGMINER_SUPPORT
Syntax options: LOGMINER SUPPORT IS ENABLED|LOGMINER SUPPORT IS DISABLED Allows additional information to be written to the after-image journal file to allow the use of the RMU Unload After_Image command. See the Oracle RMU Reference Manual for more details. Logminer support is disabled by default. The LOGMINER SUPPORT clause allows the continuous mode for LogMiner to be enabled and disabled. o LOGMINER SUPPORT IS ENABLED (CONTINUOUS) Enables continuous LogMiner. o LOGMINER SUPPORT IS ENABLED (NOT CONTINUOUS) Disables continuous LogMiner, but leaves LogMiner enabled. o LOGMINER SUPPORT IS DISABLED Disables LogMiner, including disabling continuous LogMiner.
3.56 – MAXIMUM_BUFFER_COUNT
Syntax option: MAXIMUM BUFFER COUNT IS buffer-count Specifies the number of buffers a process will write asynchronously. The default is one-fifth of the buffer pool, but not more than 10 buffers. The minimum value is 2 buffers; the maximum value can be as large as the buffer pool. You can override the number of buffers to be written asynchronously by defining the logical name RDM$BIND_BATCH_MAX. For information about how to set the values, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.57 – MAXIMUM_PAGES
Syntax option: MAXIMUM OF max-pages PAGES Specifies the maximum number of pages of each extent. The default is 9999 pages.
3.58 – METADATA_CHANGES
Syntax options: METADATA CHANGES ARE ENABLED | METADATA CHANGES ARE DISABLED Specifies whether or not data definition changes are allowed to the database. This attribute becomes effective at the next database attach and affects all ALTER, CREATE, and DROP statements (except ALTER DATABASE which is needed for database tuning) and the GRANT, REVOKE, and TRUNCATE TABLE statements. For example: SQL> CREATE DATABASE FILENAME sample; SQL> CREATE TABLE t (a INTEGER); SQL> DISCONNECT ALL; SQL> ALTER DATABASE FILENAME sample cont> METADATA CHANGES ARE DISABLED; SQL> ATTACH 'FILENAME sample'; SQL> CREATE TABLE s (b INTEGER); %RDB-E-NO_META_UPDATE, metadata update failed -RDMS-E-NOMETADATA, metadata operations are disabled The METADATA CHANGES ARE DISABLED clause prevents data definition changes to the database. The METADATA CHANGES ARE ENABLED clause allows data definition changes to the database by users granted the DBADMIN privilege. METADATA CHANGES ARE ENABLED is the default.
3.59 – MINIMUM_PAGES
Syntax option: MINIMUM OF min-pages PAGES Specifies the minimum number of pages of each extent. The default is 99 pages.
3.60 – MULTISCHEMA
Syntax options: MULTISCHEMA IS ON | MULTISCHEMA IS OFF Specifies the multischema attribute for the database. If a database has the multischema attribute, you can create multiple schemas in that database and group them within catalogs. The MULTISCHEMA IS ON option is the default for databases created with the multischema attribute. MULTISCHEMA IS OFF is the default for databases created without the multischema attribute. You can create a database using the CREATE DATABASE MULTISCHEMA IS ON clause, but you cannot use ALTER DATABASE MULTISCHEMA IS OFF to take away the multischema attribute. Once a database has the multischema attribute, you cannot change it.
3.61 – NO_BACKUP_FILENAME
Removes a previously established backup file specification.
3.62 – NO_LOCATION
This is a subclause of other clauses and has different effects, depending upon the clause in which it is used, as follows: o In the row-cache-options clause Removes the location previously specified in a LOCATION IS clause for the row cache. If you specify NO LOCATION, the row cache location becomes the directory of the database root file. The LOCATION clause of the CREATE CACHE, ADD CACHE, or ALTER CACHE clause overrides this location, which is the default for the database. o In a CREATE CACHE, ADD CACHE, or ALTER CACHE clause (row- cache-params1 clause) Removes the location previously specified in a LOCATION IS clause for the row cache backing file. If you specify NO LOCATION, the row cache location becomes the directory of the database root file. This clause is ignored if the row cache is defined to checkpoint to the database.
3.63 – NO_ROW_CACHE
Specifies that the database default is to not assign a row cache to all storage areas in the database. You cannot specify the NO ROW CACHE clause if you specify the CACHE USING clause. Alter the storage area and name a row cache to override the database default. Only one row cache is allowed for each storage area. If you do not specify the NO ROW CACHE clause or the CACHE USING clause, then the NO ROW CACHE clause is the default.
3.64 – NO_SWEEP_INTERVAL
NO SWEEP INTERVAL disables periodic timed sweeps.
3.65 – NOTIFY
Syntax options: NOTIFY IS ENABLED | NOTIFY IS DISABLED Specifies whether system notification is enabled or disabled. When the system notification is enabled, the system is notified (using the OpenVMS OPCOM facility) in the event of events such as running out of disk space for a journal. If you specify the NOTIFY IS ENABLED clause and do not specify the ALERT OPERATOR clause, the operator classes used are CENTRAL and CLUSTER. To specify other operator classes, use the ALERT OPERATOR clause. The NOTIFY IS ENABLED clause replaces any operator classes set by the RMU Set After_Journal Notify command. The default is disabled.
3.66 – NUMBER global buffers
Syntax option: NUMBER IS number-glo-buffers Specifies the total number of buffers in the global buffer pool. This number appears as "global buffer count" in RMU Dump command output. Base this value on the database users' needs and the number of attachments. The default is the maximum number of attachments multiplied by 5. NOTE Do not confuse the NUMBER IS parameter with the NUMBER OF BUFFERS IS parameter. The NUMBER OF BUFFERS IS parameter determines the default number of buffers Oracle Rdb allocates to each user's process that attaches to the database. The NUMBER OF BUFFERS IS parameter applies to, and has the same meaning for, local and global buffering. The NUMBER IS parameter has meaning only within the context of global buffering. You can override the default number of user-allocated buffers by defining a value for the logical name RDM$BIND_BUFFERS. For more information on user-allocated buffers, see Oracle Rdb7 Guide to Database Performance and Tuning. Although you can change the NUMBER IS parameter on line, the change does not take effect until the next time the database is opened.
3.67 – NUMBER_OF_BUFFERS
Syntax option: NUMBER OF BUFFERS IS number-buffers The number of buffers SQL allocates for each process using this database. Specify an unsigned integer with a value greater than or equal to 2 and less than or equal to 32,767. The default is 20 buffers.
3.68 – NUMBER_OF_CLUSTER_NODES
Syntax option: NUMBER OF CLUSTER NODES IS number-nodes Sets the upper limit on the maximum number of VMS cluster nodes from which users can access the shared database. Specify this clause only if the database named in the ALTER DATABASE statement refers to a multifile database. The default is 16 nodes. The range is 1 to 96 nodes. The actual maximum limit is the current VMS cluster node limit set by your system administrator. The Oracle Rdb root file data structures (.rdb) are mapped to shared memory, each such shared memory copy is known as an Rdb instance. When there is only one copy of shared memory containing root file information, several optimizations are enabled to reduce locking and root file I/O. activity. Specify NUMBER OF CLUSTER NODES is set to 1, or use the SINGLE INSTANCE clause to enable these optimizations. MULTIPLE INSTANCE means that the Oracle Rdb root file data structures are mapped on different system and are kept consistent through disk I/O. Such systems can not benefit from single instance optimizations. MULTIPLE INSTANCE is the default.
3.69 – NUMBER_OF_RECOVERY_BUFFERS
Syntax option: NUMBER OF RECOVERY BUFFERS IS number-buffers Specifies the number of buffers allocated to the automatic recovery process that Oracle Rdb initiates after a system or process failure. This recovery process uses the recovery-unit journal file (.ruj file extension). You can specify any number greater than or equal to 2 and less than or equal to 32,767. The default value for the NUMBER OF RECOVERY BUFFERS parameter is 20. If you have a large, multifile database and you work on a system with a large amount of memory, specify a large number of buffers. The result is faster recovery time. However, make sure your buffer pool does not exceed the amount of memory you can allocate for the pool. Use the NUMBER OF RECOVERY BUFFERS option to increase the number of buffers allocated to the recovery process. SQL> ALTER DATABASE FILENAME personnel cont> NUMBER OF RECOVERY BUFFERS IS 150; This option is used only if the NUMBER OF RECOVERY BUFFERS value is larger than the NUMBER OF BUFFERS value. For more information on allocating recovery buffers, see the Oracle Rdb Guide to Database Maintenance.
3.70 – NUMBER_OF_SWEEP_ROWS
Syntax option: NUMBER OF SWEEP ROWS IS n Specifies the number of modified rows that will be written from the row cache back to the database by the row cache server (RCS) process during a sweep operation. When the RCS is notified that a cache is "full" of modified data, the RCS starts a sweep to make space available in the cache for subsequent transactions to be able to insert rows into the cache. Oracle Corporation recommends that you initially specify the number of sweep rows to be approximately 5 percent of the total number of rows in the cache. Then monitor performance and adjust the number of sweep rows, if necessary. Allowable values must be in the range 2 through 524288. If not specified, the default is 3,000 rows.
3.71 – NUMBER_OF_USERS
Syntax option: NUMBER OF USERS IS number-users Limits the maximum number of users allowed to access the database at one time. Specify this clause only if the database named in the ALTER DATABASE statement refers to a multifile database. The default is 50 users. After the maximum is reached, the next user who tries to invoke the database receives an error message and must wait. The maximum number of users you can specify is 16368 and the minimum is 1 user. Note that number of users is defined as the number of active attachments to the database. Therefore, if a single process is running one program but that program performs 12 attach operations, the process is responsible for 12 active users. If you use the ALTER DATABASE statement to change the current number of users, the change is not journaled. Therefore, back up your database before making such a change.
3.72 – OPEN
Syntax options: OPEN IS AUTOMATIC | OPEN IS MANUAL Specifies whether or not the database must be explicitly opened before users can attach to it. The default, OPEN IS AUTOMATIC, means that any user can open a previously unopened or a closed database by attaching to it and executing a statement. The OPEN IS MANUAL option means that a privileged user must issue an explicit OPEN statement through Oracle RMU, the Oracle Rdb management utility, before other users can attach to the database. To issue the RMU Open command, you must have the RMU$OPEN privilege for the database. The OPEN IS MANUAL option limits access to databases. You will receive an error message if you specify both OPEN IS AUTOMATIC and OPEN IS MANUAL options.
3.73 – OVERWRITE
Syntax options: OVERWRITE IS ENABLED | OVERWRITE IS DISABLED Specifies whether the overwrite option is enabled or disabled. After-image journal files are used for database recovery in case of media failure and for transaction recovery as part of the fast commit feature. In some environments, only the fast commit feature is of interest and a small set of journal files can be used as a circular fast commit log with no backup of the contents required. The OVERWRITE option instructs Oracle Rdb to write over journal records that would normally be used for media recovery. The resulting set of journal files is unable to be used by the RMU Recover command for media recovery. The OVERWRITE option is ignored when only one after-image journal (.aij) file exists. Adding subsequent journal files activates the OVERWRITE option. The default is DISABLED.
3.74 – PAGE_TRANSFER
Syntax options: PAGE TRANSFER VIA DISK | PAGE TRANSFER VIA MEMORY Specifies whether Oracle Rdb transfers (flushes) pages to disk or to memory. When you specify PAGE TRANSFER VIA MEMORY, processes on a single node can share and update database pages in memory without transferring the pages to disk. It is not necessary for a process to write a modified page to disk before another process accesses the page. The default is to DISK. If you specify PAGE TRANSFER VIA MEMORY, the database must have the following characteristics: o The NUMBER OF NODES must be one, or SINGLE INSTANCE must be specified in the NUMBER OF CLUSTER NODES clause. o GLOBAL BUFFERS must be enabled. o After-image journaling must be enabled. o FAST COMMIT must be enabled. If the database does not have these characteristics, Oracle Rdb will perform page transfers via disk. For more information about page transfers, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.75 – PATHNAME path name
Identifies the database root file associated with the database. If you specify a repository path name, the path name indirectly specifies the database root file. The ALTER DATABASE statement does not change any definitions in the repository, so there is no difference in the effect of the PATHNAME and FILENAME arguments. If the database referred to in the PATHNAME or FILENAME argument has been attached, the ALTER DATABASE statement will fail with a file access conflict error.
3.76 – PERCENT_GROWTH
Syntax option: PERCENT GROWTH IS growth Specifies the percent growth of each extent. The default is 20 percent growth.
3.77 – PRESTARTED_TRANSACTIONS
Syntax options: PRESTARTED TRANSACTIONS ARE ENABLED (prestart-trans-options) PRESTARTED TRANSACTIONS ARE DISABLED Enables or disables the prestarting of transactions. Note that the keyword OFF, available in previous versions, is synonymous with DISABLED.
3.78 – READ_WRITE,READ_ONLY
The READ options of the alter-storage-area-params clause permit you to change existing storage area access as follows: o Select the READ WRITE option to change any storage area to read/write access. o Select the READ ONLY option to change any storage area to read-only access. If you want to change the read-only and read/write parameters of the RDB$SYSTEM storage area, you must specify these parameters at this point of your ALTER DATABASE statement and not in the ALTER STORAGE AREA clause. For example: SQL> -- You can change the RDB$SYSTEM storage area by altering SQL> -- the database. SQL> -- SQL> ALTER DATABASE FILENAME mf_personnel cont> READ ONLY; SQL> -- SQL> -- An error is returned if you try to change the RDB$SYSTEM storage SQL> -- area to read-only using the ALTER STORAGE AREA clause. SQL> -- SQL> ALTER DATABASE FILENAME mf_personnel cont> ALTER STORAGE AREA RDB$SYSTEM cont> READ ONLY; %RDB-E-BAD_DPB_CONTENT, invalid database parameters in the database parameter block (DPB) -RDMS-E-NOCHGRDBSYS, cannot change RDB$SYSTEM storage area explicitly SQL provides support for read-only databases and databases with one or more read-only storage areas. You can take advantage of read-only support if you have a stable body of data that is never (or rarely) updated. When the RDB$SYSTEM storage area is changed to read-only, lock conflicts occur less frequently, and the automatic updating of index and table cardinality is inhibited. Read-only databases consist of: o A read/write database root file o One or more read-only storage areas and no read/write storage areas Read-only databases can be published and distributed on CD-ROM. Read-only storage areas: o Have snapshot files but do not use them. (Data in a read-only storage area is not updated; specify a small number for the initial snapshot file size for a read-only storage area.) o Eliminate page and record locking in the read-only storage areas. o Are backed up by the RMU Backup command by default unless you explicitly state the Noread_Only qualifier, which excludes read-only areas without naming them. o Are restored by the RMU Restore command if they were previously backed up. o Are recovered by the RMU Recover command. However, unless the read-only attribute was modified, the read-only area does not change. o Are not recovered by the RMU Recover command with the Area=* qualifier, in which you are not explicitly naming the areas needing recovery, unless they are inconsistent. You use the READ ONLY option to change a storage area from read/write to read-only access. If you wanted to facilitate batch-update transactions to infrequently changed data, you would use the READ WRITE option to change a read-only storage area back to read/write. If you change a read/write storage area to read-only, you cannot specify the EXTENT, SNAPSHOT ALLOCATION, and SNAPSHOT EXTENT clauses. A database with both read/write and read-only storage areas can be fully recovered after a system failure only if after-image journaling is enabled on the database. If your database has both read/write and read-only storage areas but does not have after-image journaling enabled, perform full backup operations (including read-only areas) at all times. Doing full backup operations enables you to recover the entire database to its condition at the time of the previous backup operation. For a complete description of read-only databases and read-only storage areas, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.79 – RECOVERY_JOURNAL_(BUFFER_MEMORY)
Syntax options: BUFFER MEMORY IS LOCAL BUFFER MEMORY IS GLOBAL Specifies whether RUJ buffers will be allocated in global or local memory. The RUJ buffers used by each process are normally allocated in local virtual memory. With the introduction of row caching, these buffers now can be assigned to a shared global section (global memory) on OpenVMS, so that the recovery process can process this in-memory buffer and possibly avoid a disk access. You can define this buffer memory to be global to improve row caching performance for recovery. If row caching is disabled, then buffer memory is always local.
3.80 – RECOVERY_JOURNAL_(LOCATION)
Syntax options: RECOVERY JOURNAL (LOCATION IS directory-spec) Specifies the location, including device and directory, in which the recovery-unit journal (.ruj) file is written. Do not include network node names, file names or process-concealed logical names. The default is the current user's login device. See the Oracle Rdb Guide to Database Maintenance for more information on recovery-unit journal files. Following is an example using this clause: SQL> ALTER DATABASE FILENAME SAMPLE cont> RECOVERY JOURNAL (LOCATION IS 'SQL_USER1:[DBDIR.RECOVER]');
3.81 – RECOVERY_JOURNAL_(NO_LOCATION)
Removes a location previously defined by a RECOVERY JOURNAL LOCATION IS clause. This causes the recovery journal to revert to the default location.
3.82 – RESERVE n CACHE SLOTS
Specifies the number of row caches for which slots are reserved in the database. You can use the RESERVE CACHE SLOTS clause to reserve slots in the database root file for furture use by the ADD CACHE clause. You can only add row caches if row cache slots are available. Slots become available after you issue a DROP CACHE clause or a RESERVE CACHE SLOTS clause. You cannot reduce the number of reserved slots for row caching. If you reserve 10 slots and later reserve 5 slots, a total of 15 slots are reserved for row caches.
3.83 – RESERVE n JOURNALS
Specifies the number of journal files for which slots are to reserve in the database. The number of slots for journal files must be a positive number greater than zero. This feature is additive in nature. In other words, the number of reserved slots for journal files cannot be decreased once the RESERVE clause has been issued. If you reserve 10 slots and later reserve 5 slots, you have a total of 15 reserved slots for journal files plus 1 slot (totaling 16 reserved slots) because you initially get 1 pre-reserved slot. You must reserve slots or delete an existing journal file before you can add new journal files to the database. You cannot reserve journal files for a single-file database.
3.84 – RESERVE n SEQUENCES
Specifies the number of sequences for which slots are reserved in the database. Sequences are reserved in multiples of 32. Thus, if you specify a value less than 32 for n, 32 slots are reserved. If you specify a value of 33, 64 slots are reserved, and so on. You can use the RESERVE SEQUENCES clause to reserve slots in the database root file for future use by the CREATE SEQUENCE statement. Sequences can be created only if sequence slots are available. Slots become available after a DROP SEQUENCE statement or a RESERVE SEQUENCES clause of the ALTER DATABASE statement is executed.
3.85 – RESERVE n STORAGE AREAS
Specifies the number of storage areas for which slots are to reserve in the database. The number of slots for storage areas must be a positive number greater than zero. You can use the RESERVE STORAGE AREA clause to reserve slots in the database root file for future use by the ADD STORAGE AREA clause of the ALTER DATABASE statement. Storage areas can be added only if there are storage area slots available. Slots become available after a DROP STORAGE AREA clause or a RESERVE STORAGE AREA clause is issued. This feature is additive in nature. In other words, the number of reserved slots for storage areas cannot be decreased once the RESERVE clause is issued. If you reserve 10 slots and later reserve 5 slots, you have a total of 15 reserved slots for storage areas. You must reserve slots or delete an existing storage area before you can add new storage areas to the database. If you do not specify the RESERVE STORAGE AREA clause, the default number of reserved storage areas is zero.
3.86 – ROW_CACHE
Syntax options: ROW CACHE IS ENABLED | ROW CACHE IS DISABLED Specifies whether or not the row caching feature is enabled. Enabling row caching does not affect database operations until a cache is created and assigned to one or more storage areas. When row caching is disabled, all previously created and assigned caches remain and will be available if row caching is enabled again. The following conditions must be true in order to use row caches: o The number of cluster nodes is one o After-image journaling is enabled o Fast commit is enabled o One or more cache slots are reserved o Row caching is enabled Use the RMU Dump Header command to check if you have met the requirements for using row caches. The following command output displays a warning for every requirement that is not met: . . . Row Caches... - Active row cache count is 0 - Reserved row cache count is 1 - Sweep interval is 1 second - Default cache file directory is "" - WARNING: Maximum node count is 16 instead of 1 - WARNING: After-image journaling is disabled - WARNING: Fast commit is disabled . .
3.87 – SAME_BACKUP_FILENAME_AS_JOURNAL
During execution, the backup server assigns the same name to the backup file as it does to the journal file. This is a quick form of backup as a new file is created. NOTE Oracle Corporation recommends that you save the old journal file on tape or other media to prevent accidental purging of these files.
3.88 – SECURITY_CHECKING
Traditionally Oracle Rdb has performed security checking using the operating system security layer (for example, the UIC and rights identifiers of the OpenVMS operating system). The access control list (ACL) information stored in the database contains a granted privilege mask and a set of users represented by a unique integer (for example, a UIC). There are two modes of security checking: 1. SECURITY CHECKING IS EXTERNAL This is the default. External security checking recognizes database users as operating system user identification codes (UICs) and roles as special rights identifiers or groups. PERSONA support is enabled or disabled as follows: o SECURITY CHECKING IS EXTERNAL (PERSONA SUPPORT IS ENABLED) Enables the full impersonation of an OpenVMS user. This means the UIC and the granted right identifiers are used to check access control list permissions. o SECURITY CHECKING IS EXTERNAL (PERSONA SUPPORT IS DISABLED) Disables the full impersonation of an OpenVMS user. Only the UIC is used to check access control list permissions. This is the default for a new database, or for a database converted from a prior version of Oracle Rdb. 2. SECURITY CHECKING IS INTERNAL In this mode, Oracle Rdb records users (username and UIC) and roles (rights identifiers) in the database. The CREATE USER and CREATE ROLE statements perform this action explicitly, and GRANT will perform this implicitly. This type of database can now be moved to another system and is only dependent on the names of the users and roles. o SECURITY CHECKING IS INTERNAL (ACCOUNT CHECK IS ENABLED) The ACCOUNT CHECK clause ensures that Oracle Rdb validates the current database user with the user name (such as defined with a CREATE USER statement) stored in the database. This prevents different users with the same name from accessing the database. Therefore, this clause might prevent a breach in security. The ACCOUNT CHECK IS ENABLED clause on OpenVMS forces the user session to have the same user name and UIC as recorded in the database. o SECURITY CHECKING IS INTERNAL (ACCOUNT CHECK IS DISABLED) If you specify the ACCOUNT CHECK IS DISABLED clause, then a user with a matching UIC (also called a profile-id) is considered the same as the user even if his or her user name is different. This allows support for multiple OpenVMS users with the same UIC.
3.89 – SET_TRANSACTION_MODES
Enables only the modes specified, disabling all other previously defined modes. This is an offline operation and requires exclusive database access. For example, if a database is used for read-only access and you want to disable all other transaction modes, specify the following statement: SQL> ALTER DATABASE FILENAME mf_personnel cont> SET TRANSACTION MODES (READ ONLY); Specifying a negated txn-mode or specifying NONE disables all transaction usage. Disabling all transaction usage would be useful when, for example, you want to perform major restructuring of the physical database. Execute the ALTER DATABASE statement to re-enable transaction modes.
3.90 – SHARED_MEMORY
Syntax options: SHARED MEMORY IS SYSTEM SHARED MEMORY IS PROCESS SHARED MEMORY IS PROCESS RESIDENT Determines whether database root global sections (including global buffers when enabled) are created in system space or process space. The default is PROCESS. When you use global sections created in the process space, you and other users share physical memory and the OpenVMS operating system maps a row cache to a private address space for each user. As a result, all users are limited by the free virtual address range and each use a percentage of memory in overhead. If many users are accessing the database, the overhead can be high. When many users are accessing the database, consider using SHARED MEMORY IS SYSTEM. This gives users more physical memory because they share the system space of memory and there is none of the overhead associated with the process space of memory. The default is SHARED MEMORY IS PROCESS. When you use this clause as a cache attribute, it controls whether Oracle Rdb creates cache global sections in system space or process space. The default is PROCESS. The SHARED MEMORY clause determines whether database root global sections (including global buffers when enabled) or whether the cache global sections are created in system space or process space. The RESIDENT option extends the PROCESS option by making the global section memory resident. To enable or disable SHARED MEMORY IS PROCESS RESIDENT, the process executing the command must be granted the VMS$MEM_ RESIDENT_USER rights identifier. When this feature is enabled, the process that opens the database must also be granted the VMS$MEM_RESIDENT_USER rights identifier. Oracle Corporation recommends using the RMU Open command when utilizing this feature.
3.91 – SHUTDOWN_TIME
Syntax option: SHUTDOWN TIME IS n MINUTES Specifies the number of minutes the database system will wait after a catastrophic event before it shuts down the database. The shutdown time is the period, in minutes, between the point when the after-image journaling subsystem becomes unavailable and the point when the database is shut down. During the after- image journaling shutdown period, all database update activity is stalled. If notification is enabled with the NOTIFY IS clause, operator messages will be broadcast to all enabled operator classes. To recover from the after-image journaling shutdown state and to resume normal database operations, you must make an .aij file available for use. You can do this by backing up an existing modified journal file, or, if you have a journal file reservation available, by adding a new journal file to the after-image journaling subsystem. If you do not make a journal file available before the after-image journal shutdown time expires, the database will be shut down and all active database attachments will be terminated. The after-image journaling shutdown period is only in effect when a fixed-size .aij file is used. When a single extensible .aij file is used, the default action is to shut down all database operations when the .aij file becomes unavailable. The default is 60 minutes. The minimum value is 1 minute; the maximum value is 4320 minutes (3 days).
3.92 – SNAPSHOT_ALLOCATION
Syntax option: SNAPSHOT ALLOCATION IS snp-pages PAGES Changes the number of pages allocated for the snapshot file. The default is 100 pages. If you have disabled the snapshot file, you can set the snapshot allocation to 0 pages.
3.93 – SNAPSHOT_EXTENT
Syntax options: SNAPSHOT EXTENT IS extent-pages PAGES | SNAPSHOT EXTENT IS (extension-options) Changes the number of pages of each snapshot or storage area file extent. The default extent for storage area files is 100 pages. Specify a number of pages for simple control over the file extent. For greater control, and particularly for multivolume databases, use the MINIMUM, MAXIMUM, and PERCENT GROWTH extension options instead. If you use the MINIMUM, MAXIMUM, and PERCENT GROWTH parameters, you must enclose them in parentheses.
3.94 – SNAPSHOT_IS_ENABLED
Syntax options: SNAPSHOT IS IMMEDIATE | SNAPSHOT IS DEFERRED Specifies when read/write transactions write database changes to the snapshot file used by read-only transactions. The ENABLED IMMEDIATE option is the default and causes read/write transactions to write copies of rows they modify to the snapshot file, regardless of whether or not a read-only transaction is active. Although ENABLED IMMEDIATE is the default, if you set snapshots ENABLED DEFERRED, you must specify both ENABLED and IMMEDIATE options to return the database to the default setting. The ENABLED DEFERRED option lets read/write transactions avoid writing copies of rows they modify to the snapshot file (unless a read-only transaction is already active). Deferring snapshot writing in this manner improves the performance for the read/write transaction. However, read-only transactions that start after an active read/write transaction starts must wait for all active read/write users to complete their transactions.
3.95 – SNAPSHOT_IS_DISABLED
Specifies that snapshot writing be disabled. Snapshot writing is enabled by default. In this mode any READ ONLY transaction will be converted to READ WRITE mode automatically.
3.96 – STATISTICS_COLLECTION
Syntax options: STATISTICS COLLECTION IS ENABLED | STATISTICS COLLECTION IS DISABLED Specifies whether the collection of statistics for the database is enabled or disabled. When you disable statistics for the database, statistics are not displayed for any of the processes attached to the database. Statistics are displayed using the RMU Show Statistics command. The default is STATISTICS COLLECTION IS ENABLED. You can disable statistics using the ALTER DATABASE and IMPORT statements. For more information on the RMU Show Statistics command, see the Oracle RMU Reference Manual. You can enable statistics collection by defining the logical name RDM$BIND_STATS_ENABLED. For more information about when to use statistics collection, see the Oracle Rdb7 Guide to Database Performance and Tuning.
3.97 – storage-area-params
Parameters that control the characteristics of the storage area. For more information on the parameters, see the CREATE STORAGE_ AREA statement.
3.98 – SWEEP_INTERVAL
Syntax option: SWEEP INTERVAL IS n SECONDS Specifies the interval, in seconds, between each Record Cache Server (RCS) sweep. Allowable values must be in the range from 1 second to 3600 seconds (1 hour). The default is 1. The Record Cache Server (RCS) is a detached server process automatically invoked by the monitor when row caching is active. A sweep is one full pass through all active row cache areas to write modified rows back to the database storage areas.
3.99 – SYNONYMS_ARE_ENABLED
Adds the optional system table RDB$OBJECT_SYNONYMS that is used for the CREATE SYNONYM, ALTER . . . RENAME TO and RENAME statements. The default if omitted is disabled.
3.100 – THRESHOLD buffers option
Syntax option: THRESHOLD IS number-buffers PAGES This number represents the number of sequential buffer accesses that must be detected before prefetching is started. The default is four buffers. If you specify the THRESHOLD option, you must have also specified the DETECTED ASYNC PREFETCH clause. You receive an error if you attempt to specify the THRESHOLD option with the ASYNC PREFETCH clause.
3.101 – TRANSACTION_INTERVAL
Syntax option: TRANSACTION INTERVAL IS number-txns The TRANSACTION INTERVAL IS clause specifies the size of the transaction sequence number (TSN) range where number-txns equals the number of TSNs. Oracle Rdb uses transaction sequence numbers to ensure database integrity. When you specify NO COMMIT TO JOURNAL OPTIMIZATION, Oracle Rdb assigns TSNs to users one at a time. When you enable the journal optimization option, Oracle Rdb preassigns a range of TSNs to each user. Assigning a range of TSNs means that commit information need not be written to the database root for each transaction. Oracle Rdb writes all transaction information to the .aij file except for each user's allocated TSN range, which it writes to the root file. The transaction interval value (the TSN range) must be a number between 8 and 1024. The default value is 256. In general, if your database has few users or if all user sessions are long, select a large transaction interval. If your database has many users or if user sessions are short, select a smaller transaction interval.
3.102 – txn-modes
Specifies the transaction modes for the database. Mode Description Transaction Types [NO]READ Allows read-only transactions on the database. ONLY [NO]READ Allows read/write transactions on the database. WRITE [NO] BATCH Allows batch-update transactions on the database. UPDATE This mode executes without the overhead, or security, or a recovery-unit journal file. The batch-update transaction is intended for the initial loading of a database. Oracle Rdb recommends that this mode be disabled. Reserving Modes [NO] SHARED Allows tables to be reserved for shared mode. That [READ | is, other users can work with those tables. WRITE] [NO] Allows tables to be reserved for protected mode. PROTECTED That is, other users can read from those tables. [READ | WRITE] [NO] Allows tables to be reserved for exclusive access. EXCLUSIVE That is, other users are prevented access to those [READ | tables, even in READ ONLY transactions. WRITE] ALL Allows other users to work with all tables. NONE Allows no access to tables. For detailed information about the txn-modes, see the SET_ TRANSACTION.
3.103 – USER_LIMIT
Syntax option: USER LIMIT IS max-glo-buffers Specifies the maximum number of global buffers each user allocates. Because global buffer pools are shared by all users, you must define an upper limit on how many global buffers a single user can allocate. This limit prevents a user from defining RDM$BIND_BUFFERS to use all the buffers in the global buffer pool. The user limit cannot be greater than the total number of global buffers. The default is 5 global buffers. Decide the maximum number of global buffers a user can allocate by dividing the total number of global buffers by the total number of users for whom you want to guarantee access to the database. For example, if the total number of global buffers is 200 and you want to guarantee access to the database for at least 10 users, set the maximum number of global buffers per user to 20. For maximum performance on a VMScluster system, tune the two global buffer parameters on each node in the cluster using the RMU Open command with the Global_Buffers qualifier. Although you can change the USER LIMIT IS parameter on line, the change does not take effect until the next time the database is opened. The NUMBER IS and USER LIMIT IS parameters are the only two buffer parameters specific to global buffers. They are in effect on a per node basis rather than a per process basis.
3.104 – USER username
Syntax options: USER 'username' A character string literal that specifies the operating system user name that the database system uses for privilege checking. This clause also sets the value of the SYSTEM_USER value expression.
3.105 – USING password
Syntax options: USING 'password' A character string literal that specifies the user's password for the user name specified in the USER clause.
3.106 – WAIT option
Syntax option: WAIT n MINUTES FOR CLOSE Specifies the amount of time that Oracle Rdb waits before automatically closing a database. If anyone attaches during that wait time, the database is not closed. The default value for n is zero (0) if the WAIT clause is not specified. The value for n can range from zero (0) to 35,791,394. However, Oracle Rdb does not recommend using large values.
3.107 – WORKLOAD_COLLECTION
Syntax options: WORKLOAD COLLECTION IS ENABLED | WORKLOAD COLLECTION IS DISABLED Specifies whether or not the optimizer records workload information in the system table RDB$WORKLOAD. The WORKLOAD COLLECTION IS ENABLED clause creates this system table if it does not exist. If you later disable workload collection, the RDB$WORKLOAD system table is not deleted, nor is the data deleted. A workload profile is a description of the interesting table and column references used by queries in a database work load. When workload collection is enabled, the optimizer collects and records these references in the RDB$WORKLOAD system table. This work load is then processed by the RMU Collect Optimizer- Statistics command which records useful statistics about the work load. These workload statistics are used by the optimizer at run time to deliver more accurate access strategies. Workload collection is disabled by default.
4 – Examples
Example 1: Changing a read/write storage area to a read-only storage area This example changes the SALARY_HISTORY storage area from a read/write storage area to a read-only storage area. SQL> ALTER DATABASE FILENAME mf_personnel cont> ALTER STORAGE AREA salary_history cont> READ ONLY; Example 2: Adding multiple, fixed-size journal files This example demonstrates reserving slots for journal files, enabling the journaling feature, and adding multiple, fixed-size journal files. SQL> CREATE DATABASE FILENAME test cont> RESERVE 5 JOURNALS cont> CREATE STORAGE AREA sa_one cont> ALLOCATION IS 10 PAGES; SQL> DISCONNECT ALL; SQL> SQL> ALTER DATABASE FILENAME test cont> JOURNAL IS ENABLED cont> ADD JOURNAL AIJ_ONE cont> FILENAME aij_one cont> BACKUP FILENAME aij_one cont> ADD JOURNAL AIJ_TWO cont> FILENAME aij_two cont> BACKUP FILENAME aij_two cont> ; You should place journal files and backup files on disks other than those that contain the database. Example 3: Reserving and using slots for storage areas This example demonstrates reserving slots for storage areas and adding storage areas to the database that utilizes those slots. Use the SHOW DATABASE statement to see changes made to the database. SQL> CREATE DATABASE FILENAME sample cont> RESERVE 5 STORAGE AREAS cont> CREATE STORAGE AREA RDB$SYSTEM cont> FILENAME sample_system cont> -- cont> -- Storage areas created when the database is created do not use cont> -- the reserved storage area slots because this operation is being cont> -- executed off line. cont> -- cont> ; %RDMS-W-DOFULLBCK, full database backup should be done to ensure future recovery SQL> -- SQL> -- Reserving storage area slots is not a journaled activity. SQL> -- SQL> -- To use the reserved slots, you must alter the database and SQL> -- add storage areas. SQL> -- SQL> DISCONNECT ALL; SQL> ALTER DATABASE FILENAME sample cont> ADD STORAGE AREA SAMPLE_1 cont> FILENAME sample_1 cont> ADD STORAGE AREA SAMPLE_2 cont> FILENAME sample_2; Example 4: Reserving Slots for Sequences This example shows that reserving extra sequences in the database adds to the existing 32 that are provided by default, and the count rounded up to the next multiple of 32 (that is, 64). $ SQL$ ALTER DATABASE FILENAME MF_PERSONNEL RESERVE 10 SEQUENCES; %RDMS-W-DOFULLBCK, full database backup should be done to ensure future recovery $ RMU/DUMP/HEADER=SEQUENCE MF_PERSONNEL *------------------------------------------------------------------------------ * Oracle Rdb V7.1-200 15-AUG-2003 14:54:26.55 * * Dump of Database header * Database: USER2:[DOCS.WORK]MF_PERSONNEL.RDB;1 * *------------------------------------------------------------------------------ Database Parameters: Root filename is "USER2:[DOCS.WORK]MF_PERSONNEL.RDB;1" Sequence Numbers... . . . Client sequences... - 64 client sequences have been allocated - 0 client sequences in use Example 5: Adding and Enabling a Row Cache on OpenVMS The MF_PERSONNEL database is altered to add a row cache, apply it to several storage areas and enable row caching. The example further assumes that after image journals have already been defined for the database, they are required for the JOURNAL IS ENABLED clause to succeed. SQL> /* ***> Prepare the database for ROW CACHE, include extra ***> capacity for later additions ***> */ SQL> alter database cont> filename MF_PERSONNEL cont> number of cluster nodes is 1 cont> journal is ENABLED (fast commit is enabled) cont> reserve 20 cache slots cont> row cache is ENABLED cont> cont> /* ***> Create a physical cache for all the employee rows ***> */ cont> add cache EMPIDS_RCACHE cont> shared memory is SYSTEM cont> row length is 126 bytes cont> cache size is 204 rows cont> checkpoint updated rows to database cont> cont> /* ***> Apply the cache to each of the relevant storage areas ***> */ cont> alter storage area EMPIDS_LOW cont> cache using EMPIDS_RCACHE cont> alter storage area EMPIDS_MID cont> cache using EMPIDS_RCACHE cont> alter storage area EMPIDS_OVER cont> cache using EMPIDS_RCACHE cont> ; %RDMS-W-DOFULLBCK, full database backup should be done to ensure future recovery Example 6: Establishing a Timeout Value for Prestarted Transactions SQL> ALTER DATABASE cont> FILENAME SAMPLE cont> PRESTARTED TRANSACTIONS ARE ENABLED cont> (WAIT 90 SECONDS FOR TIMEOUT) cont> ; Example 7: Altering a Database Specifying the SINGLE INSTANCE Option This example prepares a database to be run in a 4 node GALAXY cluster. The SINGLE INSTANCE clause is used to enable special optimizations that are available because of the galaxy shared memory. SQL> alter database cont> filename MF_PERSONNEL cont> galaxy support is ENABLED cont> number of cluster nodes is 4 (single instance); Example 8: Disabling storage if snapshot rows The following example demonstrates using SQL to modify the "C1" cache to disable storage of snapshot rows in cache and to modify the "C5" cache to enable storage of snapshot rows in the cache with a snapshot cache size of 12345 rows: SQL> ALTER DATABASE FILE EXAMPLE_DB cont> ALTER CACHE C1 cont> ROW SNAPSHOT IS DISABLED; cont> ALTER CACHE C5 cont> ROW SNAPSHOT IS ENABLED (CACHE SIZE IS 12345 ROWS); Example 9: Using the SWEEP INTERVAL clause Here is an example of using the SWEEP INTERVAL clause. SQL> ALTER DATABASE FILENAME MF_PERSONNEL cont> ROW CACHE IS ENABLED (SWEEP INTERVAL IS 100 seconds) cont> ; SQL> attach 'filename MF_PERSONNEL'; SQL> show database rdb$dbhandle Default alias: Oracle Rdb database in file MF_PERSONNEL . . . Row Cache is Enabled Row cache: sweep interval is 100 seconds Row cache: No Location Row cache: checkpoint updated rows to backing file . . .