1  File_Area_Key_Properties
   The file definition, area, and key properties define the physical
   characteristics of a Record Management Services (RMS) database
   file.

   In most cases, the properties correspond to the RMS file and
   allocation control field blocks (FABs or XABs). CDO does not
   provide properties corresponding to the RMS record access block
   attributes (RABs).

   See the OpenVMS documentation on RMS for detailed descriptions
   and the values accepted for each property listed in this
   chapter.
  

2  file_def_prop

   Format

     { ALLOCATION  numeric-literal                                }
     { BUCKET_SIZE  numeric-literal                               }
     { MT_BLOCK_SIZE  numeric-literal                             }
     {                                                            }
     { GLOBAL_BUFFER_COUNT  numeric-literal                       }
     { MAX_RECORD_NUMBER  numeric-literal                         }
     { MAX_RECORD_SIZE  numeric-literal                           }
     {                                                            }
     { FILE_PROCESSING_OPTIONS  [ file-processing-options ]  ,... }
     { FOP  [ file-processing-options ]  ,...                     }
     { ORGANIZATION  file-organization-options                    }
     {                                                            }
     { file-access-block-properties                               }
 

3  Parameters
 

4  numeric-literal

   Specifies a positive integer.
 

4  file-processing-options



   [ BEST_TRY_CONTIGUOUS ]
   [ CONTIGUOUS          ]
   [ CREATE_IF           ]
   [ DEFERRED_WRITE      ]
   [ DELETE_ON_CLOSE     ]
   [ MAXIMIZE_VERSION    ]
   [ MT_CLOSE_REWIND     ]
   [ MT_CURRENT_POSITION ]
   [ MT_NOT_EOF          ]
   [ MT_OPEN_REWIND      ]
   [ NO_DIRECTORY_ENTRY  ]
   [ NON_FILE_STRUCTURED ]
   [ PRINT_ON_CLOSE      ]
   [ READ_CHECK          ]
   [ SEQUENTIAL_ONLY     ]
   [ SUBMIT_ON_CLOSE     ]
   [ SUPERSEDE           ]
   [ TEMPORARY           ]
   [ TRUNCATE_ON_CLOSE   ]
   [ USER_FILE_OPEN      ]
   [ WRITE_CHECK         ]

   Define optional file operations for a program. The file
   processing options fall into the following seven functional
   categories:

   o  Allocation and extension options

   o  File disposition options

   o  File name parsing modifiers

   o  Magnetic tape processing options

   o  Nonstandard processing options

   o  Performance options

   o  Reliability options
 

4  file-organization-options



   { INDEXED    }
   { RELATIVE   }
   { SEQUENTIAL }

   Define the organization of the file. The default value for the
   file organization option is SEQUENTIAL.
 

4  file-access-block-attributes



   { EXTENSION numeric-literal                   }
   { CONTROL_FIELD_SIZE numeric-literal          }
   { WINDOW_SIZE numeric-literal                 }
   { LOGICAL_NAME_MODE access-mode               }
   { CHANNEL_ACCESS_MODE access-mode             }
   { ACCESS [ file-access-control-options ] ,... }
   { FAC [ file-access-control-options ] ,...    }
   { CARRIAGE_CONTROL carriage-control-options   }
   { BLOCK_SPAN                                  }
   { FORMAT record-format-options                }
   { SHARING [ share-options ] ,...              }

   Define file access characteristics and certain run-time options.
 

4  access-mode



   { NONE      }
   { EXECUTIVE }
   { SUPER     }
   { USER      }

   Defines an access mode for a channel. NONE is the default value,
   which is interpreted by RMS as the executive mode.
 

4  file-access-control-options



   { BLOCK_IO  }
   { RECORD_IO }
   { DELETE    }
   { GET       }
   { PUT       }
   { TRUNCATE  }
   { UPDATE    }

   Define the type of record access operations that a program can
   perform.
 

4  carriage-control-options



   { CARRIAGE_RETURN }
   { FORTRAN         }
   { PRINT           }

   Define record control information for a record. CARRIAGE_RETURN
   is the default value for most OpenVMS programs.
 

4  record-format-options



   { FIXED     }
   { STREAM    }
   { STREAM_CR }
   { STREAM_LF }
   { UNDEFINED }
   { VARIAABLE }
   { VFC       }

   Define the format for all records in a file.
 

4  share-options



   { DELETE         }
   { GET            }
   { MULTISTREAM    }
   { PROHIBIT       }
   { PUT            }
   { UPDATE         }
   { USER_INTERLOCK }

   Define the type of record operations that a program can perform
   when sharing access to a file with other programs.
 

3  Description
   File definition properties define file characteristics and
   certain run-time options for a logical RMS database element.

   For a description and valid values for a particular keyword, see
   the OpenVMS documentation on RMS.

   For a mapping of CDO keywords to symbolics, see RMS_Keyword_
   Mapping_Tables.
 

3  Examples

 CDO>  DEFINE RMS_DATABASE EMPLOYEE_
INFO DESCRIPTION IS "INFORMATION ON"
 cont>   "CURRENT EMPLOYEE".
 cont>   RECORD EMPLOYEE_REC.
 cont>   FILE_DEFINITION
 cont>     ORGANIZATION INDEXED
 cont>     CHANNEL_ACCESS_MODE SUPER
 cont>     CARRIAGE_CONTROL CARRIAGE_RETURN
 cont>     ACCESS  RECORD_IO
 cont>     FILE_PROCESSING_OPTIONS BEST_TRY_CONTIGUOUS
 cont>     FORMAT VARIABLE
 cont>     SHARING GET, USER_INTERLOCK.
 cont>   AREAS.
 cont>     AREA 0
 cont>       ALLOCATE 1000
 cont>       BUCKET_SIZE 10
 cont>       EXTENSION 100
 cont>       CONTIGUOUS.
 cont>     AREA 1
 cont>       ALLOCATE 1000
 cont>       BUCKET_SIZE 1
 cont>       EXTENSION 100
 cont>       BEST_TRY_CONTIGUOUS.
 cont>     AREA 2
 cont>       ALLOCATE 1000
 cont>       BUCKET_SIZE 1
 cont>       EXTENSION 100
 cont>       BEST_TRY_CONTIGUOUS.
 cont>   END AREAS.

 cont>   KEYS.
 cont>     KEY 0
 cont>       DATA_AREA 0
 cont>       INDEX_AREA 0
 cont>       SEGMENT EMP_ID IN EMPLOYEE_REC.
 cont>     KEY 1
 cont>       DUPLICATES
 cont>       DATA_AREA 1
 cont>       INDEX_AREA 2
 cont>       SEGMENT LAST_NAME IN EMPLOYEE_REC.
 cont>   END KEYS.
 cont> END EMPLOYEE_INFO RMS_DATABASE.

     This example is the complete logical RMS database definition
     for EMPLOYEE_INFO. Seven file definition properties appear in
     the DEFINE RMS_DATABASE command:

     o  The option for file organization is INDEXED.

     o  The channel access mode is SUPER.

     o  The carriage control option is CARRIAGE_RETURN, although it
        is not necessary to code this because CARRIAGE_RETURN is the
        default.

     o  The type of record access operation this program can perform
        is RECORD_IO.

     o  An optional file processing operation is BEST_TRY_
        CONTIGUOUS.

     o  Record format for this definition is VARIABLE.

     o  The types of record operations that this program can perform
        when sharing access to a file with other programs are GET
        and USER_INTERLOCK.
 

2  area_properties

   Format

     { EXACT_POSITIONING           }
     { ANY_CYLINDER                }
     { BEST_TRY_CONTIGUOUS         }
     {                             }
     { CONTIGUOUS                  }
     { POSITION position-type      }
     { VOLUME numeric-literal      }
     {                             }
     { ALLOCATE numeric-literal    }
     { BUCKET_SIZE numeric-literal }
     { EXTENSION numeric-literal   }
     {                             }
 

3  Parameters
 

4  position-type

   Defines the alignment of an allocated area. The default alignment
   value is NONE. For more information, see RMS_Keyword_Mapping_Tables.
 

4  numeric-literal

   Specifies a positive integer.
 

3  Description
   Area properties provide additional control over file or area
   space allocation on disk devices to optimize performance.

   You usually include areas using indexed files. A file can contain
   up to 255 areas. Define areas in numerical order, beginning with
   0.

   For a description and valid values for a particular keyword, see
   the OpenVMS documentation on RMS.

   For a mapping of CDO keywords to symbolics, see RMS_Keyword_
   Mapping_Tables.
 

3  Examples

   1.CDO>  DEFINE RMS_DATABASE EMPLOYEE_INFO DESCRIPTION IS "INFORMATION ON"
     cont> "CURRENT EMPLOYEE".
     cont>   RECORD EMPLOYEE_REC.
        .
        .
        .
     cont>   AREAS.
     cont>     AREA 0
     cont>       ALLOCATE 1000
     cont>       BUCKET_SIZE 10
     cont>       EXTENSION 100
     cont>       CONTIGUOUS.
     cont>     AREA 1
     cont>       ALLOCATE 1000
     cont>       BUCKET_SIZE 1
     cont>       EXTENSION 100
     cont>       BEST_TRY_CONTIGUOUS.
     cont>     AREA 2
     cont>       ALLOCATE 1000
     cont>       BUCKET_SIZE 1
     cont>       EXTENSION 100
     cont>       BEST_TRY_CONTIGUOUS.
     cont>   END AREAS.
        .
        .
        .
     cont> END EMPLOYEE_INFO RMS_DATABASE.
     CDO>

     This example shows the syntax for defining the ALLOCATE,
     BUCKET_SIZE, EXTENSION, CONTIGUOUS, and BEST_TRY_CONTIGUOUS
     properties for three areas in the EMPLOYEE_INFO RMS database
     element.
 


   2.CDO>  DEFINE RMS_DATABASE MORE_EMPLOYEE_INFO
     cont>   "DESCRIPTION IS " DATA ON CURRENT EMPLOYEES ".
     cont>   RECORD EMPLOYEE_REC.
     cont>     FILE_DEFINITION
     cont>     AREA 1
     cont>     POSITION NONE.
        .
        .
        .
     cont> END MORE_EMPLOYEE_INFO RMS_DATABASE.
     CDO>

     This example shows the syntax that defines the NONE position
     type option for the area property POSITION in the MORE_
     EMPLOYEE_INFO RMS database element.
 

2  key_properties

   Format

     { DUPLICATES                    }
     { CHANGES                       }
     { NULL_KEY                      }
     {                               }
     { NULL_VALUE null-value         }
     { DATA_AREA area-number         }
     { DATA_FILL numeric-literal     }
     {                               }
     { DATA_KEY_COMPRESSION          }
     { DATA_RECORD_COMPRESSION       }
     { INDEX_AREA area-number        }
     {                               }
     { INDEX_COMPRESSION             }
     { INDEX_FILL numeric-literal    }
     { LEVEL1_INDEX_AREA area-number }
     {                               }
     { NODATA_KEY_COMPRESSION        }
     { NODATA_RECORD_COMPRESSION     }
     { NOINDEX_COMPRESSION           }
     {                               }
     { PROLOG numeric-literal        }
     { SEGMENT within-name-clause    }
     { SORTED BY ASCENDING           }
     {                               }
     { SORTED BY DESCENDING          }
 

3  Parameters
 

4  null-value

   Specifies a null key value for an alternate index. This value is
   either an integer or a single character within quotation marks.
 

4  area-number

   Specifies a positive integer that corresponds to the number of a
   previously defined area.
 

4  numeric-literal

   Specifies a positive integer. See the OpenVMS documentation on
   RMS for the valid values for a particular keyword. For a mapping
   of CDO keywords to the corresponding RMS symbolic field offset,
   see RMS_Keyword_Mapping_Tables.
 

4  within-name-clause

   field-name { IN record-name } ...

   Specifies the field or record names that are part of a segmented
   key. A segmented key allows you to define a key that accesses
   noncontiguous fields in a record. The record name is the same
   name that defines the data structure of the RMS database in the
   DEFINE RMS_DATABASE command.
 

3  Description
   Key properties define the characteristics of a key in an indexed
   file. You define keys in numerical order, starting with 0. By
   default, Key 0 always has a value of DATA_AREA 0.

   A segmented key allows you to define a key that accesses non-
   contiguous fields in a record. You can specify from 2 to 8
   segments for each segmented key in an indexed file. For example:

   o  A field in a record

   o  A field in a record that is in a record

   o  A field in a structure in a record

   You must specify a segment for each key you define. A segmented
   key can contain up to 8 segments.

   The field element or elements specified by the keyword SEGMENT
   determine the data type of the key. A key with only 1 segment can
   point to a field that has any of the following RMS data types:

      DSC$K_DTYPE_B
      DSC$K_DTYPE_BU
      DSC$K_DTYPE_W
      DSC$K_DTYPE_WU
      DSC$K_DTYPE_L
      DSC$K_DTYPE_LU
      DSC$K_DTYPE_Q
      DSC$K_DTYPE_QU
      DSC$K_DTYPE_P
      DSC$K_DTYPE_T

   See the OpenVMS documentation on RMS for more information on
   valid RMS data types.

   Each segment of a key can contain up to 255 characters. The
   sum of all characters for all key segments must not exceed 255
   characters.

   When defining a segment, you cannot use a field that is in the
   variant portion of a record.

   If you specify NULL_VALUE without specifying NULL_KEY, CDO
   automatically specifies NULL_KEY. If you specify NULL_KEY without
   specifying NULL_VALUE, the default value for NULL_VALUE is
   0. When you display a RMS database element with a NULL_VALUE
   property, the null value appears as a decimal value.

   For a description and valid values for a particular keyword, see
   the OpenVMS documentation on RMS.

   For a mapping of CDO keywords to symbolics, see RMS_Keyword_
   Mapping_Tables.
 

3  Examples

 CDO>  DEFINE RMS_DATABASE EMPLOYEE_
INFO DESCRIPTION IS "INFORMATION ON"
 cont> "CURRENT EMPLOYEE".
 cont>   RECORD EMPLOYEE_REC.
    .
    .
    .
 cont>   KEYS.
 cont>     KEY 0
 cont>       DATA_AREA 0
 cont>       INDEX_AREA 0
 cont>       SEGMENT EMP_ID IN EMPLOYEE_REC.
 cont>     KEY 1
 cont>       DUPLICATES
 cont>       DATA_AREA 1
 cont>       INDEX_AREA 2
 cont>       SEGMENT LAST_NAME IN EMPLOYEE_REC.
 cont>   END KEYS.
 cont> END EMPLOYEE_INFO RMS_DATABASE.
 CDO>

     This example shows the syntax for defining the DATA_AREA,
     INDEX_AREA, SEGMENT, and DUPLICATES key properties in the
     EMPLOYEE_INFO RMS database element.
  

2  RMS_Keyword_Mapping_Tables
   The following tables show the mapping of the different keywords
   used when creating a logical RMS database in a CDO dictionary.


   Table 4-1 Mapping of Keywords to Symbolic Field Offsets

   Keyword                     Symbolic Field Offset

                            Area Properties

   ALLOCATE                    XAB$L_ALQ
   ANY_CYLINDER                XAB$V_ONC
   BEST_TRY_CONTIGUOUS         XAB$V_CBT
   BUCKET_SIZE                 XAB$B_BKZ
   CONTIGUOUS                  XAB$V_CTG
   EXACT_POSITIONING           XAB$V_HRD
   EXTENSION                   XAB$W_DEQ
   POSITION                    XAB$B_ALN
   VOLUME                      XAB$W_VOL



                      File Access Block Properties

   ACCESS                      FAB$B_FAC
   BLOCK_SPAN                  FAB$V_BLK
   CARRIAGE_CONTROL            FAB$B_RAT
   CHANNEL_ACCESS_MODE         FAB$V_CHAN_MODE
   CONTROL_FIELD_SIZE          FAB$B_FSZ
   EXTENSION                   FAB$W_DEQ
   FAC                         FAB$B_FAC
   FORMAT                      FAB$B_RFM
   LOGICAL_NAME_MODE           FAB$V_LNM_MODE
   SHARING                     FAB$B_SHR
   WINDOW_SIZE                 FAB$B_RTV


                       File Definition Properties

   ALLOCATION                  FAB$L_ALQ
   BUCKET_SIZE                 FAB$B_BKS
   FILE_PROCESSING_OPTIONS     FAB$L_FOP
   FOP                         FAB$L_FOP
   GLOBAL_BUFFER_COUNT         FAB$W_GBC
   MAX_RECORD_NUMBER           FAB$L_MRN
   MAX_RECORD_SIZE             FAB$W_MRS
   MT_BLOCK_SIZE               FAB$W_BLS
   ORGANIZATION                FAB$B_ORG



                             Key Properties

   ASCENDING                   XAB$B_DTP
   CHANGES                     XAB$V_CHG
   DATA_AREA                   XAB$B_DAN
   DATA_FILL                   XAB$W_DFL
   DATA_KEY_COMPRESSION        XAB$V_KEY_NCMPR
   DATA_RECORD_COMPRESSION     XAB$V_DAT_NCMPR
   DESCENDING                  XAB$B_DTP
   DUPLICATES                  XAB$V_DUP
   INDEX_AREA                  XAB$B_IAN
   INDEX_COMPRESSION           XAB$V_IDX_NCMPR
   INDEX_FILL                  XAB$W_IFL
   LEVEL1_INDEX_AREA           XAB$B_LAN
   NODATA_KEY_COMPRESSION      XAB$V_KEY_NCMPR
   NODATA_RECORD_COMPRESSION   XAB$V_DAT_NCMPR
   NOINDEX_COMPRESSION         XAB$V_IDX_NCMPR
   NULL_KEY                    XAB$V_NUL
   NULL_VALUE                  XAB$B_NUL
   PROLOG                      XAB$B_PROLOG

   Mapping of Keywords to Symbolic Constants shows the mapping of
   keywords to symbolic constants.

   Table 4-2 Mapping of Keywords to Symbolic Constants

                      Symbolic
   Keyword            Constant       Constant Type

                              Access Mode

   EXECUTIVE          PSL$C_EXEC     FAB$V_CHAN_MODE
   NONE (default)     0              FAB$V_CHAN_MODE
   SUPER              PSL$C_SUPER    FAB$V_CHAN_MODE
   USER               PSL$C_USER     FAB$V_CHAN_MODE


                          File Access Control

   BLOCK_IO           FAB$V_BIO      FAB$B_FAC
   DELETE             FAB$V_DEL      FAB$B_FAC
   GET                FAB$V_GET      FAB$B_FAC
   PUT                FAB$V_PUT      FAB$B_FAC
   RECORD_IO          FAB$V_BRO      FAB$B_FAC
   TRUNCATE           FAB$V_TRN      FAB$B_FAC
   UPDATE             FAB$V_UPD      FAB$B_FAC



                           File Organization

   INDEXED            FAB$C_INX      FAB$B_ORG
   RELATIVE           FAB$C_REL      FAB$B_ORG
   SEQUENTIAL         FAB$C_SEQ      FAB$B_ORG
   (default)


                             Position Type

   CYLINDER           XAB$C_CYL      XAB$B_ALN
   FILE_ID            XAB$C_RFI      XAB$B_ALN
   LOGICAL            XAB$C_LBN      XAB$B_ALN
   NONE (default)     XAB$C_ANY      XAB$B_ALN
   VIRTUAL            XAB$C_VBN      XAB$B_ALN



                             Record Format

   FIXED              FAB$C_FIX      FAB$B_RFM
   STREAM             FAB$C_STM      FAB$B_RFM
   STREAM_CR          FAB$C_STMCR    FAB$B_RFM
   STREAM_LF          FAB$C_STMLF    FAB$B_RFM
   UNDEFINED          FAB$C_UDF      FAB$B_RFM
   VARIABLE           FAB$C_VAR      FAB$B_RFM
   VFC                FAB$C_VFC      FAB$B_RFM

   Mapping of Keywords to Symbolic Bit Offsets shows the mapping of
   keywords to symbolic bit offsets.

   Table 4-3 Mapping of Keywords to Symbolic Bit Offsets

                      Symbolic Bit
   Keyword            Offset         Symbolic Bit Offset Type

                        Carriage Control Options

   CARRIAGE_RETURN    FAB$V_CR       FAB$B_RAT
   (default)
   FORTRAN            FAB$V_FTN      FAB$B_RAT
   PRINT              FAB$V_PRN      FAB$B_RAT


            File Processing Options-Allocation and Extension

   BEST_TRY_          FAB$V_CBT      RMS
   CONTIGUOUS
   CONTIGUOUS         FAB$V_CTG      RMS
   TRUNCATE_ON_CLOSE  FAB$V_TEF      RMS



                  File Processing Options-Disposition

   DELETE_ON_CLOSE    FAB$V_DLT      RMS
   PRINT_ON_CLOSE     FAB$V_SPL      RMS
   SUBMIT_ON_CLOSE    FAB$V_SCF      RMS
   TEMPORARY          FAB$V_TMD      RMS
   NO_DIRECTORY_      FAB$V_TMP      RMS
   ENTRY


             File Processing Options-Name Parsing Modifiers

   CREATE_IF          FAB$V_CIF      RMS
   MAXIMIZE_VERSION   FAB$V_MXV      RMS
   SUPERSEDE          FAB$V_SUP      RMS



                 File Processing Options-Magnetic Tape

   MT_NOT_EOF         FAB$V_NEF      RMS
   MT_CURRENT_        FAB$V_POS      RMS
   POSITION
   MT_CLOSE_REWIND    FAB$V_RWC      RMS
   MT_OPEN_REWIND     FAB$V_RWO      RMS


                  File Processing Options-Nonstandard

   NON_FILE_          FAB$V_NFS      RMS
   STRUCTURED
   USER_FILE_OPEN     FAB$V_UFO      RMS



                  File Processing Options-Performance

   DEFERRED_WRITE     FAB$V_DFW      RMS
   SEQUENTIAL_ONLY    FAB$V_SQO      RMS


                  File Processing Options-Reliability

   READ_CHECK         FAB$V_RCK      RMS
   WRITE_CHECK        FAB$V_WCK      RMS



                             Share Options

   DELETE             FAB$V_SHRDEL   FAB$B_SHR
   GET                FAB$V_SHRGET   FAB$B_SHR
   MULTISTREAM        FAB$V_MSE      FAB$B_SHR
   PROHIBIT           FAB$V_NIL      FAB$B_SHR
   PUT                FAB$V_SHRPUT   FAB$B_SHR
   UPDATE             FAB$V_SHRUPD   FAB$B_SHR
   USER_INTERLOCK     FAB$V_UPI      FAB$B_SHR

   Mapping of CDO Area Properties to RMS Symbolic Field Offsets
   and Mapping of CDO Position Type Options to XAB$B_ALN Symbolic
   Constants show the mapping of area properties keywords to
   symbolic field offsets and constants.

   Table 4-4 Mapping of CDO Area Properties to RMS Symbolic Field
             Offsets

   CDO Property                RMS Symbolic Field Offset

   ALLOCATE                    XAB$L_ALQ
   ANY_CYLINDER                XAB$V_ONC
   BEST_TRY_CONTIGUOUS         XAB$V_CBT
   BUCKET_SIZE                 XAB$B_BKZ
   CONTIGUOUS                  XAB$V_CTG
   EXACT_POSITIONING           XAB$V_HRD
   EXTENSION                   XAB$W_DEQ
   POSITION                    XAB$B_ALN
   VOLUME                      XAB$W_VOL

   Table 4-5 Mapping of CDO Position Type Options to XAB$B_ALN
             Symbolic Constants

   CDO Option                  Symbolic Constant

   CYLINDER                    XAB$C_CYL
   FILE_ID                     XAB$C_RFI
   LOGICAL                     XAB$C_LBN
   NONE (default)              XAB$C_ANY
   VIRTUAL                     XAB$C_VBN

   Mapping of CDO Key Properties to RMS Symbolic Field Offsets
   shows the mapping of key properties keywords to symbolic field
   offsets.

   Table 4-6 Mapping of CDO Key Properties to RMS Symbolic Field
             Offsets

   CDO Property                RMS Symbolic Field Offset

   ASCENDING                   XAB$B_DTP
   DESCENDING                  XAB$B_DTP
   DUPLICATES                  XAB$V_DUP
   CHANGES                     XAB$V_CHG
   NULL_KEY                    XAB$V_NUL
   NULL_VALUE                  XAB$B_NUL
   DATA_AREA                   XAB$B_DAN
   DATA_FILL                   XAB$W_DFL
   DATA_KEY_COMPRESSION        XAB$V_KEY_NCMPR
   DATA_RECORD_COMPRESSION     XAB$V_DAT_NCMPR
   INDEX_AREA                  XAB$B_IAN
   INDEX_COMPRESSION           XAB$V_IDX_NCMPR
   INDEX_FILL                  XAB$W_IFL
   LEVEL1_INDEX_AREA           XAB$B_LAN
   NODATA_KEY_COMPRESSION      XAB$V_KEY_NCMPR
   NODATA_RECORD_COMPRESSION   XAB$V_DAT_NCMPR
   NOINDEX_COMPRESSION         XAB$V_IDX_NCMPR
   PROLOG                      XAB$B_PROLOG