Creates a transfer definition and stores it in the transfer
database. A transfer definition contains all the information
necessary to select a set of records from the source database
and to define a target database. A transfer definition also can
contain the views to be defined on the target database and the
command procedures to be executed before and after the execution
of the transfer.
A source database for extraction transfers can be Oracle Rdb, or
a database accessed through one of the Rdb Transparent Gateways.
For replication transfers, the source database must be an Oracle Rdb
database.
NOTE
The DEFINE TRANSFER statement, unlike the SQL CREATE
TRANSFER statement, cannot be used to define transfers
to existing databases (including replication transfers
with the NO DELETE attribute). It also does not provide
a checkpoint clause. Furthermore, unlike the SQL CREATE
TRANSFER statement, the RDO utility does not support the
MIA character set attributes. It is possible to create a
transfer definition using RDO and name a database containing
MIA features. However, the character set attributes of the
resulting target database might not be correct.
Use of RDO is recommended only when you want to manipulate
databases that use only the DEC_MCS character set for
text data.
1 – Format
(B)0[m[4mDEFINE[m [4mTRANSFER[m qq> transfer-name qqwqqq> [4mREPLICATION[m qqqqqqqqqwqqk
tqqq> [4mEXTRACTION[m qqqqqqqqqqu x
mqqq> [4mEXTRACTION[m [4mROLLUP[m qqqj x
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqqwq>qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqq> [4mTO[m qq> file-spec qk
mq> [4mDESCRIPTION[m IS q> /* text */ qj x
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqwq>qqqqqqqqqqqqqqqqqqqqqqqwqwqwq>qqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqwqk
mq>target-db-param-clauseqj x tq>move-relations-clause qqqqqqqu x x
x tq>move-views-clause qqqqqqqqqqqu x x
x mq>move-relations-rollup-clauseqj x x
mqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqj x
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqqwqqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqwqqqqqqqqqqqqqqqqqqqqqqqqqqk
mqqq> transfer-file-options-clause qqj x
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqq> [4mEND[m qqqwqqqqqqqqq>qqqqqqqqqwqqwqqqqqqq>qqqqqqwqqqqqqq> .
mq> transfer-name qqj mq> [4mTRANSFER[m qqj
1.1 – transfer-name
Identifies the transfer by name. The transfer name must be unique
across all of the nodes at a given VAXcluster or VMScluster site
because a single transfer database serves all nodes in a cluster
environment. For example, you could have two users on the same
server attempting to create a transfer called PERS_REC. One user
would succeed while the other would receive an error message
saying that the transfer already exists. To ensure that names
are unique, you may wish to make the user identifier part of each
transfer name.
A valid transfer name has the following characteristics:
o Has a length from 1 to 31 bytes (octets).
o Can be formed using any of the set of ASCII characters:
A B C ... Z 0 1 2 ... 9 _ $ a b c ... z
Lower case letters may be used, but are treated as if they
were uppercase.
o Cannot include letters with diacritical marks (which are used
in European languages for instance).
o The first character of the name must either be a letter or the
dollar sign ($). However, Oracle Corporation recommends that you do not
use dollar signs in a transfer name; dollar signs are reserved
for special use by Digital Equipment Corporation.
The transfer-name parameter is required.
1.2 – REPLICATION
Specifies that Replication Option create a replication database
at the target site. When a replication transfer executes,
Replication Option creates a database at the target site
during the initial execution and maintains a connection to that
target database so the source can supply updates to the target.
Subsequent transfers involve only those modifications that have
been made to the selected records in the source database. (If the
target and source database should become inconsistent with each
other, you can use the REINITIALIZE TRANSFER statement to restore
consistency.)
In addition, the execution of a replication transfer generally
creates special-purpose relations in the source database and the
target database to handle updating. Because the source database
is modified with the addition of these system relations, the
transfer definer's account needs the DEFINE access right to the
source database itself.
Users are expected to access the replication target database
only to retrieve data. Applications should not attempt to store,
modify, or erase values in records of the replication database.
Although data values should not be manipulated in a replication
database, you can modify the target database by defining views
and indexes, and adding access rights.
1.3 – EXTRACTION
Specifies that Replication Option create an extraction
database at the target site. Because each extraction database
is independent of the source database, users at the target
directory can access extraction databases with read/write as
well as read-only transactions. Each time an extraction mode
transfer executes, Replication Option creates a new version of
the target database and transfers a complete copy of the selected
records to the target node.
Indexes, constraints, and access rights are not transferred
when the target database is created. Similarly, primary key
and foreign key attributes for a particular relation are
not transferred because key attributes are implemented as
constraints. Once the target database has been created, you can
define indexes, constraints, and triggers for it and modify the
access rights.
1.4 – EXTRACTION_ROLLUP
Specifies that Replication Option create an extraction rollup
database at the target site by transferring selected relations
and fields from one or more source databases into a single
target database. An extraction rollup database is created at the
target site, and Replication Option reads data from the source
databases and stores the data in a target database.
Each time an extraction rollup transfer is executed, Replication
Option creates a new version of the target database and
transfers to it a complete copy of the selected records.
The EXTRACTION ROLLUP option in the DEFINE TRANSFER statement has
the following characteristics and limitations:
o Replication Option issues an error message if you do not
enter a MOVE RELATION clause or a SELECT FIELDS list in a
move-relations-rollup-clause.
o You must refer to each source database in the DEFINE TRANSFER
statement by its database handle.
o On the target database, relation names and field names must
be unique. Consequently, all target relations of the same name
must have the same definition, and all target fields of the
same name must have the same data type. If the definitions
or data types differ, Replication Option issues an error
message and the transfer fails.
o If any database specified in the transfer definition is on a
node that is not available, Replication Option places the
transfer in a waiting-to-retry state. Replication Option
will retry the transfer at the time specified for retry in the
schedule definition.
o If any of the source nodes specified in the transfer
definition fail during the transfer, the transfer will also
fail. Replication Option will retry the transfer at the time
specified for retry in the schedule definition.
o If the transfer fails, the retry will start at the beginning,
not where the transfer left off.
Indexes, constraints, and access rights are not transferred
when the target database is created. Similarly, primary key
and foreign key attributes for a particular relation are
not transferred because key attributes are implemented as
constraints. Once the target database has been created, you can
define indexes, constraints, and triggers for it and modify the
access rights.
1.5 – text
A text string that allows you to associate a comment with the
transfer definition. The text string, together with other
parts of the transfer definition, appears in the SHOW TRANSFER
DEFINITION display. The DESCRIPTION IS clause is optional.
1.6 – file-spec
Designates a file specification for the target database, which
is an Oracle Rdb database. Replication Option uses the file
specification to create and access the target database. You can
use either a full or partial file specification or a logical
name. The file-spec parameter is required. If you do not specify
the node, device, or directory, Replication Option assumes the
SYS$LOGIN of the user defining the transfer. If the file type
is not .RDB, the transfer will fail during the creation of the
target database. The default file type is .RDB.
When you specify the name of a remote node as part of the file
specification, you can include an access control list (ACL) for
login. However, the most effective method of allowing access to a
target node uses proxy accounts.
If you use DECnet/OSI note that Replication Option expects node
names in file specifications to be from one to six characters
long. DECnet/OSI permits node names to be much longer than this.
In order to use Replication Option in a DECnet/OSI environment,
you must define and use short synonyms for the long node names.
Node name synonyms can be registered either in a local or
distributed name service database. For details on establishing
node name synonyms, refer to the documentation for DECnet/OSI.
Note that the file specification is resolved at run time. All
logical names used for the file-spec parameter are resolved
within the copy process after it executes the transfer definer's
login initialization file, LOGIN.COM. If the target database
name is a logical symbol name, when it is translated, the default
directory is the one pointed to by SYS$LOGIN.
Replication Option makes no attempt to verify whether a
database or file of the same name already exists in the target
directory. When you issue a duplicate file specification,
Replication Option creates a second file with the same name, but a
higher version number.
If the database system (Oracle Rdb) returns an error while
attempting to create a database in the target directory, the
copy process writes the error in the copy process log file and
returns the error status to the transfer monitor.
1.7 – target-db-param-clause
(B)0[mtarget-db-param-clause =
qqqwqwq>qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqwqwqq>
x tq> [4mALLOCATION[m IS qqqqqqqq> number-pages qq> PAGES qqqqu x
x tq> [4mPAGE[m [4mSIZE[m IS qqq> page-blocks qqqqqq> BLOCKS qqqqqqu x
x tq> [4mNUMBER[m OF [4mBUFFERS[m IS qq> number-buffers qqqqqqqqqqqu x
x tq> [4mNUMBER[m OF [4mUSERS[m IS qqqq> number-users qqqqqqqqqqqqqu x
x tq> [4mBUFFER[m [4mSIZE[m IS qq> buffer-blocks qqq> BLOCKS qqqqqqu x
x tq> [4mEXTENT[m IS qqqqqqqqqqwq> ext-pages qqq> PAGES qqqwqqu x
x x mq> (multi-vol-ext-clause) qj x x
x tq> [4mSNAPSHOT[m IS qqqqwq> [4mENABLED[m qwq> [4mIMMEDIATE[m qqwqwqqqu x
x x x mq> [4mDEFERRED[m qqj x x x
x x mq> [4mDISABLED[m qqqqqq>qqqqqqqqqqqj x x
x tq> [4mSNAPSHOT[m [4mALLOCATION[m IS q> snp-pages q> PAGES qqqqqqu x
x mq> [4mSNAPSHOT[m [4mEXTENT[m IS qw> ext-pages qqqq> PAGES qqqqwqj x
x m> (multi-vol-ext-clause) qqqj x
mqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqj
Enables you to specify values for the parameters that affect
the creation of the target database. This clause uses syntax
similar to the Oracle Rdb DEFINE DATABASE statement. However,
Replication Option does not support all the parameters that DEFINE
DATABASE supports. Replication Option uses the values provided
in this clause to create the target database.
1.7.1 – number-pages
The number of database pages initially allocated to the target
database. Oracle Rdb automatically extends the allocation to handle
the loading of data and subsequent expansion. The default is 400
pages. If you are transferring a large number of records, a large
page allocation helps to prevent fragmented records.
1.7.2 – page-blocks
The size in blocks of each database page in the target directory.
Page size is allocated in 512-byte blocks. The default is two
blocks (1024 bytes). If your largest record has more than
approximately 950 bytes, you can specify more blocks for each
page to prevent records from being fragmented.
1.7.3 – number-buffers
The number of buffers Oracle Rdb allocates for each process using
the target database. The value must be greater than zero. The
default is 20 buffers.
1.7.4 – number-users
The maximum number of users allowed to access the target database
at one time. 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 for access. The largest number of
users you can specify is 508, and the smallest is 1.
1.7.5 – buffer-blocks
The number of blocks Oracle Rdb allocates for each buffer. The value
must be greater than zero. If you do not specify this parameter,
Oracle Rdb uses a buffer size that is three times the page size
value.
1.7.6 – ext-pages
The number of pages of each target database extent. This
parameter provides direct control over the extent of the
target database. For greater control, and particularly for
multivolume databases, use the MINIMUM, MAXIMUM, and PERCENT
GROWTH parameters of the multi-vol-ext-clause instead. The
default extent is 100 pages.
1.7.7 – ENABLED_IMMEDIATE
Specifies that READ_WRITE transactions write previously updated
copies of records they modify to the snapshot file, regardless
of whether a read-only transaction is active. Snapshot writing
is enabled immediately by default. With snapshots enabled, users
or applications can read from either the snapshot file or the
database file itself.
1.7.8 – ENABLED_DEFERRED
Specifies that READ_WRITE transactions not write previously
updated copies of records they modify to the snapshot file unless
a READ_ONLY transaction is already active. READ_ONLY transactions
that attempt to start after an active READ_WRITE transaction
must wait for all active READ_WRITE users to complete their
transactions. With snapshots enabled, users or applications can
read from either the snapshot file or the database file itself.
1.7.9 – DISABLED
Specifies that snapshot writing be disabled. There is usually
some performance gain when snapshot writing is disabled because
Oracle Rdb does not need to perform write operations to the snapshot
file during updates to the database.
You should not disable snapshots for replication databases.
Although users are expected only to retrieve data from the
replication database, retrieval can occur in either READ_ONLY
or READ_WRITE transactions.
1.7.10 – snp-pages
The number of pages allocated for the snapshot file. The default
is 100 pages. After the target database has been created, you can
use the RDO CHANGE DATABASE statement to truncate the snapshot
file. To truncate the file, specify an allocation size smaller
than the current snapshot file size.
1.7.11 – multi-vol-ext-clause
(B)0[mmulti-vol-ext-clause =
qqqqq> [4mMINIMUM[m OF qq> min-pages qqq> PAGES, qk
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqq> [4mMAXIMUM[m OF qq> max-pages qqq> PAGES, qk
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mqq> [4mPERCENT[m [4mGROWTH[m IS qqq> growth qqqq>
1.7.11.1 – min-pages
The minimum number of pages of each target database extent. The
default is 100 pages.
1.7.11.2 – max-pages
The maximum number of pages of each target database extent. The
default is 10,000 pages.
1.7.11.3 – growth
The percent of growth for each target database extent. The
default is 20 percent growth.
1.8 – move_relations_clause
(B)0[mmove-relations-clause =
qwqq> [4mMOVE[m [4mRELATIONS[m [4mALL[m qqqqqqqqqqqqqqqqqqqqqqq>qqqqqqqqqqqwqqqq>
x x
mqwqq> [4mMOVE[m [4mRELATION[m qqwqqqqqqqqqqqqqqqwqq> rse qqqqqqk x
x mq> /* text */ qj x x
x lqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqj x
x mq> [4mSELECT[m [4mFIELDS[m qwqq> [4mALL[m qqqqqqqq>qqqqqqqwqqwqqj
x mwq> select-field-name qwj x
x mqqqqqqqq , <qqqqqqqqqqj x
mqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq ; <qqqqqqqqqqqqqqqqqqqj
Selects the records Replication Option transfers to the target
database during an extraction or a replication transfer. The
records selected for replications are specified with a restricted
form of a record selection expression (RSE). You must specify a
move-relations-clause for each user relation moved to the target
database. If you do not include a move-relations-clause, Replication
Option assumes the default, MOVE RELATIONS ALL.
When you specify a view in a MOVE RELATION clause, the records
selected by that view are created as a relation in the target
database. You can also transfer views using the move-views-
clause.
You must have READ privilege for the relations of an Oracle Rdb
source database that you specify in a MOVE RELATION clause or
a MOVE RELATIONS ALL clause. For databases accessed through the
Rdb Transparent Gateways, Replication Option does not check for
READ privilege for views.
1.8.1 – MOVE_RELATIONS_ALL
Allows you to have Replication Option select all records and
fields from all user relations, excluding views, that are in
the source database at the time the transfer is defined. If
you wish to move views, you must use the move-views-clause or
the MOVE RELATION clause. Fields defined with a COMPUTED_BY
clause are restricted to those that use the value expressions
shown in the value-expr syntax diagram in this section. If a
field is not defined by a supported value expression, you will
receive a warning message, and the COMPUTED_BY fields will not be
transferred.
If you define a transfer on a source database that is itself a
target extraction database, do not use the MOVE RELATIONS ALL
clause. An error will result during transfer execution because
Replication Option will attempt to define the DDAL$VINTAGE
relation in the new target database twice. The second transfer
would create a DDAL$VINTAGE relation in the target database.
Then, using the MOVE RELATIONS ALL clause, it would attempt to
copy the DDAL$VINTAGE relation that already exists in the source
database. To avoid this error, specify explicitly each relation
to be moved instead of using MOVE RELATIONS ALL.
Do not use the MOVE RELATIONS ALL statement for an extraction
rollup transfer. If you use the MOVE RELATIONS ALL statement to
define an extraction rollup transfer, the transfer will fail on
execution. Instead, you must name the individual relations you
want to transfer to the extraction rollup target.
1.8.2 – text
A text string that allows you to associate a comment with the
transfer definition. The text string, together with other parts
of the transfer definition, appears in the SHOW DEFINITION
display. The DESCRIPTION IS clause is optional.
1.8.3 – rse
The record selection expression (RSE) used to identify records
from the source database that Replication Option includes in
a record stream and transfers to the target database. The RSE
specifies conditions that individual records must satisfy in
order to be included in the transfer to the target database.
Replication Option supports COMPUTED_BY fields named in an RSE
if the fields are defined using the value expressions shown in
the value-expr syntax diagram in this section. If the fields are
not defined by a supported value expression, you will receive a
fatal error message.
In extraction, extraction rollup, and replication transfers,
you can use a relation-clause and with-clause. In extraction and
extraction rollup transfers, you can also use a first-clause,
reduce-clause, and sort-clause.
1.8.4 – SELECT_FIELDS_ALL
Enables you to include every field in a specific relation. Fields
defined with a COMPUTED_BY clause are restricted to those that
use the value expressions shown in the value-expr syntax diagram
in this section. If a field is not defined by a supported value
expression, you will receive a warning message, and the COMPUTED_
BY fields will not be transferred. You cannot use the SELECT
FIELDS ALL statement for an extraction rollup transfer.
1.8.5 – select-field-name
(B)0[mselect-field-name =
qqqqqqqq> context-variable qq> . qqq> field-name qqqqq>
Allows you to name a specific field or group of fields you want
moved to the target database. You can specify only one SELECT
clause for each MOVE clause. Replication Option moves only the
named fields to the target database. If you do not specify SELECT
FIELDS ALL, the select-field-name clause is required.
Replication Option supports COMPUTED_BY fields named in the
select-field-name clause if the fields are defined using the
value expressions shown in the value-expr syntax diagram in
this section. If the fields are not defined by a supported value
expression, you will receive a fatal error message.
1.9 – move-views-clause
(B)0[mmove-views-clause =
qqqq> [4mMOVE[m [4mVIEWS[m qqwqq> [4mALL[m qqqqqqqqqqqwqqq>
mwq> view-name qqwqqj
mqqqqqq , <qqqqqqj
Selects the views Replication Option defines on the target
database during an extraction or a replication transfer. All the
relations, views, and fields on which the transferred views are
based must also be explicitly or implicitly named in the DEFINE
TRANSFER statement. The transfer definition will fail if any
underlying relation, view, or field is not named when you define
the transfer. Note that, if you omit the move-relations-clause,
relations are implicitly named in the transfer definition because
MOVE RELATIONS ALL is the default.
If you specify a view name in this clause, the view definition
is transferred to the target database. You can include only one
move-views-clause in a DEFINE TRANSFER statement. However, you
can specify two or more views in that move-views-clause.
Transferring views is limited by the following restrictions:
o COMPUTED_BY fields
Replication Option transfers those COMPUTED_BY fields that
depend only on the values of the relation in which the field
is defined. Views that contain unsupported COMPUTED_BY fields
cannot be transferred. If views that contain unsupported
COMPUTED_BY fields are specified in the move-views-clause
of a DEFINE TRANSFER statement, the transfer definition fails.
You need to redefine the transfer, excluding the views that
refer to the unsupported COMPUTED_BY fields.
o READ privilege for the view
For a view in an Oracle Rdb database to be transferred, Replication
Option requires that you have Oracle Rdb READ privilege for
the view and for the underlying relations. If you do not have
READ privilege for views you specify in the move-views-clause
of a DEFINE TRANSFER statement, the transfer will fail. You
need to obtain READ privilege for these views before including
them in a DEFINE TRANSFER statement.
For databases accessed through the Rdb Transparent Gateways,
Replication Option does not check for READ privilege for views.
You can also move views with the move-relations-clause. However,
when you use the move-relations-clause to move a view, the view
becomes a relation in the target database.
1.9.1 – view-name
The name of the view Replication Option transfers to the target
during a transfer. If you do not specify a view name, Replication
Option assumes the default, MOVE VIEWS ALL.
1.10 – move-relations-rollup-clause
(B)0[mmove-relations-rollup-clause =
qwq> [4mMOVE[m [4mRELATION[m qqqqwqqqqqqqq>qqqqqqqqwq> rse qqqqwqqqqwq>
x mq> / *text*/qqqqqj x x
x lqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqj x
x mqqwqqqqqqqqqqqqqqqqqqqqqq>qqqqqqqqqqqqqqqqqqqwqk x
x mq> [4mINTO[m [4mRELATION[m qqqq> relation-name qqqqqj x x
x lqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqj x
x mq> [4mSELECT[m [4mFIELDS[m qqwqq> select-field-name qqqqqwqwqj
x mqqqqqqqqqq , <qqqqqqqqqqqqqj x
mqqqqqqqqqqqqqqqqqqqqqqqqqqq ; <qqqqqqqqqqqqqqqqqqqqqqqj
Selects the records Replication Option transfers into the
target database from a number of source databases during an
extraction rollup transfer. The move-relations-rollup-clause
has the following restrictions:
o Replication Option requires you to invoke each source
database with a different database handle. You must then use
these handles in the move-relations-rollup-clause to identify
tables of each source database.
o The move-relations-rollup-clause must be used with the
EXTRACTION ROLLUP parameter.
Rollup transfers must be extractions. If you attempt to use
the move-relations-rollup-clause with a replication transfer,
the transfer definition will fail.
o The MOVE RELATIONS ALL and SELECT FIELDS ALL clauses are not
allowed in rollup transfers.
1.10.1 – rse
For more information on record selection expression, select the
subtopic RSE under the DEFINE_TRANSFER Format subtopic.
1.10.2 – select-field-name
(B)0[mselect-field-name =
qqqqqqqq> context-variable qq> . qqq> field-name qqqqq>
Allows you to name a specific field or group of fields you want
moved to the target database. You can specify only one SELECT
clause for each MOVE clause. Replication Option moves only the
named fields to the target database. If you do not specify SELECT
FIELDS ALL, the select-field-name clause is required. All fields
that you name in the record selection expression (RSE) must also
be named in the SELECT FIELDS clause.
Replication Option supports COMPUTED_BY fields named in the
select-field-name clause if the fields are defined using the
value expressions shown in the value-expr syntax diagram in
this section. If the fields are not defined by a supported value
expression, you will receive a fatal error message.
1.11 – transfer-file-options-clause
(B)0[mtransfer-file-options-clause
qwqwqqqqqqqqqqqqqqqqqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqqqwqqqqqqq>
x tqq> [4mPROLOGUE[m FILE IS qqqq> prologue-file-spec qqqqqqqu
x tqq> [4mNOPROLOGUE[m qqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqqqu
x tqq> [4mEPILOGUE[m FILE IS qqqq> epilogue-file-spec qqqqqqqu
x tqq> [4mNOEPILOGUE[m qqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqqqu
x tqq> [4mLOG[m FILE [4mIS[m qqqqqqqqq> log-file-spec qqqqqqqqqqqqu
x mqq> [4mNOLOG[m qqqqqqqqqqqqqqq>qqqqqqqqqqqqqqqqqqqqqqqqqqqu
mqqqqqqqqqqqqqqqqqqqqqqqqqqq<qqqqqqqqqqqqqqqqqqqqqqqqqqqj
The DCL command procedures to be executed before or after
transfers and the OpenVMS file where logging information related
to the transfer execution is located.
1.11.1 – prologue-file-spec
The name of the prologue command procedure file to be run before
the transfer executes. This file runs at the beginning of the
first execution of the transfer and of all subsequent transfers.
The prologue file is a DCL command file. You can include a
version number and a remote node name in the file specification.
The name is resolved when the transfer is defined.
The prologue-file-spec parameter is optional. If you do not
include this parameter, Replication Option assumes that
NOPROLOGUE is in effect. The default file type is .COM. The
default directory for the prologue file is SYS$LOGIN.
If your file specification includes a node name and you are using
DECnet/OSI, note that Replication Option expects node names
in file specifications to be from one to six characters long.
DECnet/OSI permits node names to be much longer than this. In
order to use Replication Option in a DECnet/OSI environment,
you must define and use short synonyms for the long node names.
Node name synonyms can be registered either in a local or
distributed name service database. For details on establishing
node name synonyms, refer to the documentation for DECnet/OSI.
1.11.2 – epilogue-file-spec
The name of the epilogue command procedure file to be run after
the transfer executes. This file runs after the first execution
of the transfer and after all subsequent transfers. The epilogue
file is a DCL command file. You can include a version number or a
remote node name in the file specification. The name is resolved
when the transfer is defined.
The epilogue-file-spec parameter is optional. If you do not
include this parameter, Replication Option assumes that
NOEPILOGUE is in effect. The default file type is .COM. The
default directory for the epilogue file is SYS$LOGIN.
If your file specification includes a node name and you are using
DECnet/OSI, note that Replication Option expects node names
in file specifications to be from one to six characters long.
DECnet/OSI permits node names to be much longer than this. In
order to use Replication Option in a DECnet/OSI environment,
you must define and use short synonyms for the long node names.
Node name synonyms can be registered either in a local or
distributed name service database. For details on establishing
node name synonyms, refer to the documentation for DECnet/OSI.
1.11.3 – log-file-spec
The OpenVMS file where the Replication Option copy process
writes any logging information related to the execution of the
transfer. If you include a version number or a node name in the
file specification, Replication Option returns an error.
Replication Option creates a new log file every time a transfer
executes. The name is resolved when the transfer is defined.
The log-file-spec parameter is optional. If you do not include
this parameter, Replication Option assumes that NOLOG is in
effect. The default file type is .LOG. The default directory for
the log file is SYS$LOGIN.
1.12 – RSE
(B)0[mrse =
qqwqqqqqqqq>qqqqqqqqwqq> relation-clause qq>qqqqqqqqqqqqqqqqqqqqk
mq> first-clause qj x
lqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
mwqqqqqqq>qqqqqqqqwqwqqqqqqqq>qqqqqqqqqqwqqwqqqqqqqq>qqqqqqqqwqqq>
mq> with-clause qj mq> reduce-clause qqj mq> sort-clause qqj
The record selection expression (RSE) used to identify records
from the source database that Replication Option includes in
a record stream and transfers to the target database. The RSE
specifies conditions that individual records must satisfy in
order to be included in the transfer to the target database.
Replication Option supports COMPUTED_BY fields named in an RSE
if the fields are defined using the value expressions shown in
the value-expr syntax diagram in this section. If the fields are
not defined by a supported value expression, you will receive a
fatal error message.
In extraction, extraction rollup, and replication transfers,
you can use a relation-clause and with-clause. In extraction and
extraction rollup transfers, you can also use a first-clause,
reduce-clause, and sort-clause.
1.12.1 – first-clause
(B)0[mfirst-clause =
qqqq> [4mFIRST[m qqqqqq> value-expr qqqqqqqqqqq>
(B)0[mvalue-expr =
qqqqqqqwqqqq> database-field qqqqqqwqq>
tqqqq> quoted-string qqqqqqqu
tqqqq> numeric-literal qqqqqu
tqqqq> arithmetic-expr qqqqqu
tqqqq> missing-value qqqqqqqu
tqqqq> concat-expr qqqqqqqqqu
tqqqq> ( value-expr ) qqqqqqu
mqqqq> q qq> value-expr qqqj
Specifies how many records are selected from the record stream
formed by the record selection expression (RSE). You can only
use the first-clause for an extraction or an extraction rollup
transfer. If you specify a first-clause for a replication
transfer, Replication Option issues an error message.
1.12.2 – relation-clause
(B)0[mrelation-clause =
q> context-variable q> [4mIN[m wqqqqqqqq>qqqqqqqqwq> relation-name q>
m> db-handle q> . j
The context variables and relations to be included in the record
stream or loop.
If you specify a view name in the relation-clause, the moved view
becomes a relation in the target database.
The context-variable supplies a temporary name to identify the
record stream. Once you have associated a context-variable with
a relation, you use the context-variable to refer to fields from
that relation.
The db-handle is a host variable or name used to refer to a
specific database you have invoked.
In extraction or replication transfers, you should not use
database handles in the RSE of a MOVE RELATION clause. Replication
Option returns an error message if you include a database
handle in the RSE. However, in an extraction rollup transfer, you
must use database handles in the RSE to specify the relation or
Replication Option will return an error message.
1.12.3 – with-clause
(B)0[mwith-clause =
qqqqqqqqqqqqq> [4mWITH[m qqqqqqqqqq> conditional-expr qqqqqqqqqqq>
(B)0[mconditional-expr =
qwqqq> conditional-expr qq> [4mAND[m qq> conditional-expr qqqwqqq>
tqqq> conditional-expr qq> [4mOR[m qqq> conditional-expr qqqu
tqqqqqqqqqqqqqqqqqqqqqqqq> [4mNOT[m qq> conditional-expr qqqu
tqqq> value-expr1 qq> rel-oper qq> value-expr2 qqqqqqqqu
tqqq> between-clause qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu
tqqq> containing-clause qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu
tqqq> matching-clause qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqu
tqqq> starting-with-clause qqqqqqqqqqqqqqqqqqqqqqqqqqqqu
mqqq> missing-clause qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqj
The with-clause contains a conditional expression that allows
you to specify conditions that must be true for a record to be
included in a record stream.
1.12.4 – reduce-clause
(B)0[mreduce-clause =
qqqqqqqqqqqqqq> [4mREDUCED[m [4mTO[m qqqwqqqqq> value-expr qqqwqqqqq>
mqqqqqqqq , <qqqqqqqqqj
(B)0[mvalue-expr =
qqqqqqqwqqqq> database-field qqqqqqwqq>
tqqqq> quoted-string qqqqqqqu
tqqqq> numeric-literal qqqqqu
tqqqq> arithmetic-expr qqqqqu
tqqqq> missing-value qqqqqqqu
tqqqq> concat-expr qqqqqqqqqu
tqqqq> ( value-expr ) qqqqqqu
mqqqq> q qq> value-expr qqqj
Allows you to eliminate duplicate values for fields in a record
stream. You can use the reduce-clause for an extraction or an
extraction rollup transfer. If you specify a reduce-clause for
a replication transfer, Replication Option issues an error
message.
1.12.5 – sort-clause
(B)0[msort-clause =
qqq> [4mSORTED[m [4mBY[m qqwqwqqqqqqqqqqqqqqqqqqwqqqqq> value-expr qqwqqq>
x tqq> [4mASCENDING[m qqqqu x
x mqq> [4mDESCENDING[m qqqj x
mqqqqqqqqqqqqqqqqqqqqqq , <qqqqqqqqqqqqqqqj
(B)0[mvalue-expr =
qqqqqqqwqqqq> database-field qqqqqqwqq>
tqqqq> quoted-string qqqqqqqu
tqqqq> numeric-literal qqqqqu
tqqqq> arithmetic-expr qqqqqu
tqqqq> missing-value qqqqqqqu
tqqqq> concat-expr qqqqqqqqqu
tqqqq> ( value-expr ) qqqqqqu
mqqqq> q qq> value-expr qqqj
Allows you to sort the records in the record stream by the values
of specific fields. You can sort the records according to a
value expression called a sort key. The sort key determines the
order of the records in the record stream. You can use the sort-
clause for an extraction or an extraction rollup transfer. If
you specify a sort-clause for a replication transfer, Replication
Option issues an error message.
Specifying ASCENDING (the default) causes the records to be
sorted in ascending order. Specifying DESCENDING causes Oracle Rdb
to sort the records in descending order.
The value expression specifies the sort value. This value is
called the sort key.
2 – More
After you issue the DEFINE TRANSFER statement, the transfer does
not execute until one of the following events occurs:
- The time specified in the corresponding DEFINE SCHEDULE
statement arrives
- You issue a START TRANSFER NOW statement
You cannot alter a transfer using RDO. You must either drop
the transfer and re-create it, or use the SQL ALTER TRANSFER
statement.
You must have READ privilege for the relations and views of a
Oracle Rdb source database that you specify in a DEFINE TRANSFER
statement. Replication Option returns an error message when you
specify relations and views in a DEFINE TRANSFER statement for
which you do not have READ privilege. Replication Option does not
check for READ privilege for relations and views when you specify
a database accessed through the Rdb Transparent Gateways.
You must execute the DEFINE TRANSFER statement outside of the
scope of a transaction. If you issue this statement when a
transaction is outstanding, Replication Option returns an error
message.
You can refer to relations, fields, and views in a DEFINE
TRANSFER statement either implicitly or explicitly. When you
include either the MOVE RELATIONS ALL, SELECT FIELDS ALL, or
MOVE VIEWS ALL clause, you refer to relations, fields, or views
implicitly. Replication Option uses the current definitions
of the relations, fields, and views in the source database and
stores those names explicitly in the transfer definition. You
refer to relations, fields, and views explicitly when you include
the MOVE RELATION, SELECT FIELDS, or MOVE VIEWS clauses and
supply specific relation, field, or view names.
All fields that you name in the record selection expression (RSE)
of the DEFINE TRANSFER statement must also be included in the
SELECT FIELDS clause. If you do not name the fields explicitly
in the SELECT FIELDS select-field-name statement or implicitly
in the select-field-name clause, Replication Option returns
an error message when the transfer executes, indicating that the
field name is not found in the symbol table.
Replication Option transfers those COMPUTED_BY fields that
depend only on the values of a relation in which the field is
defined. You cannot transfer views that contain unsupported
COMPUTED_BY fields. If views that contain unsupported COMPUTED_
BY fields are specified in the move-views-clause of a DEFINE
TRANSFER statement, the transfer definition fails. You need to
redefine the transfer, excluding the views that refer to the
unsupported COMPUTED_BY fields.
Replication Option allows you to transfer views in two ways:
o Using the move-views-clause
Replication Option transfers the definition of the view
when you specify MOVE VIEWS view-name or MOVE VIEWS ALL. You
must also explicitly or implicitly name in the DEFINE TRANSFER
statement all the relations, views, or fields on which the
transferred view definitions are based. The transfer will fail
if any underlying relations, views, or fields are not named.
o Using the move-relations-clause
Replication Option transfers a view by creating a relation
in the target database containing the view's records when
you use the MOVE RELATION clause. This method improves query
performance in the target database. For example, you can
achieve the effect of a CROSS clause by transferring a view
that is a CROSS in the source.
You specify the relations you wish to move in the move-relations-
clause and the views in the move-views-clause of the DEFINE
TRANSFER statement. When you are doing an extraction rollup
transfer, you specify the relations you wish to move in the
move-relations-rollup-clause of the DEFINE TRANSFER statement.
The same clause can occur in a DEFINE TRANSFER statement no more
than once. You cannot specify the same relation or view more than
once in the move clauses. If a relation name or view name appears
in more than one move clause, Replication Option returns an
error.
Individual move-relations clauses are separated by semicolons,
as indicated in the syntax diagrams. You can implement the move-
relations-clause in two ways:
o Specify MOVE RELATIONS ALL
o Specify a series of relations separated by semicolons
The move-relations-clause has the following characteristics and
limitations:
o All fields in each move-relations-clause must reside in the
same relation.
o You cannot name the same relation in more than one MOVE clause
of a single transfer definition.
The move-relations-rollup-clause has the following
characteristics and limitations:
o All fields in each move-relations-rollup-clause must reside in
the same relation.
o You cannot name the same relation in more than one MOVE clause
of a single transfer definition.
o For each relation of a move-relations-rollup-clause that you
enter, you can supply a target relation specification in the
form of an INTO RELATION clause. You can create one or many
relations in the target database from several source database
relations by renaming the target relations in the transfer
definition.
o You cannot specify MOVE RELATIONS ALL or SELECT FIELDS ALL in
a move-relations-rollup-clause. When you specify these clauses
in the DEFINE TRANSFER statement, the transfer will fail at
the time of definition.
The format of record selection expressions (RSE) that you can
include in a transfer definition for extraction and extraction
rollup transfers is more limited than the RSE allowed by RDO. You
cannot include the following expressions and clauses in the RSE
of the MOVE clause of the DEFINE TRANSFER statement:
o CROSS clause
o ANY operator
o UNIQUE operator
o Host variable
o Statistical expressions
o FIRST FROM expression
o Database key values
o Segmented string expressions
You can specify FIRST clauses, REDUCED clauses, and SORTED BY
clauses in the RSE of both extraction and extraction rollup
transfers. You can achieve the effect of a CROSS clause in an
extraction or an extraction rollup transfer by transferring a
relation, that is itself a view, defined in the source database
as a cross of two or more relations.
The next example shows an extraction transfer definition that
specifies the FIRST, REDUCED, and SORTED BY clauses in the RSE.
The transfer also achieves the capability of a CROSS clause by
moving a view, CURRENT_SALARY. In the source database, CURRENT_
SALARY is a cross of the EMPLOYEES, SALARY_HISTORY, and JOB_
HISTORY relations.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER SALARY_HISTORY EXTRACTION
cont> TO NEWNODE::NEWDISK:[NEWDIR]EMP_SALARY
cont> MOVE RELATION FIRST 1000 E IN EMPLOYEES
cont> REDUCED TO E.LAST_NAME
cont> SORTED BY ASCENDING E.LAST_NAME
cont> SELECT FIELDS ALL;
cont> MOVE RELATION C IN CURRENT_SALARY SELECT FIELDS ALL
cont> LOG IS FIRSTDISK:[FIRSTDIR]EMP_SALARY.LOG
cont> END.
Because you cannot use certain expressions to identify required
records, the resulting groups of records transferred to the
extraction database might be larger than the number of extracted
records users will actually use. However, local users on
the target node can then include precise RSEs accessing the
extraction database.
The format of an RSE that you can include in the transfer
definition for replication transfers is more limited than the
RSE allowed by RDO. You cannot include the following forms of
expressions or clauses in the RSE of the MOVE clause of the
DEFINE TRANSFER statement:
o FIRST clause
o CROSS clause
o REDUCED clause
o SORTED BY clause
o ANY operator
o UNIQUE operator
o Host variable
o Statistical expressions
o FIRST FROM expression
o Database key values
o Segmented string expression
Because you cannot use certain expressions to identify required
records, the resulting groups of records transferred to the
replication database might be larger than the number of records
users will actually use. However, local users on the target node
can then include precise record selection expressions when using
RDO to access the replication database.
If a transfer fails during execution, the transfer will begin
again at the next scheduled retry time if the failure results
from a nonfatal error.
This next transfer will start from the beginning to ensure
consistency with any updates that might have been made to the
source database.
Replication Option transfers only definitions for the database,
fields, and relations specified in the transfer definition. If
the source database includes additional database entities such
as indexes, constraints, or access control lists, these are not
transferred to the target database. You must either directly
access the individual target database and explicitly define these
entities or run command procedures to define the entities after
the transfer executes.
When relations specified in the transfer definition are created
in the target database, they are given the access control lists
(ACLs) that have the Oracle Rdb default values. You can change the
ACLs in the target database after it has been created.
Replication Option does not support SQL ANSI-style privileges.
Target databases that Replication Option creates use the
default Oracle Rdb ACL-style privileges. SQL ANSI-style privileges
assigned to a source database are not copied to or preserved on
target databases during transfers.
In a transfer definition, you can use logical symbol names to
name the source database file, the target database file, the
copy process log file, and the prologue and the epilogue command
procedure files. However, Replication Option treats these file
names differently:
o Source database file logical names
If the source file name is a logical symbol that translates
to a standard OpenVMS file name specification, Replication
Option performs the logical name translation. The
SHOW TRANSFER DEFINITION statement shows the source file
name in its translated form. The logical symbol can also
translate into strings that, in turn, contain logical symbols.
As long as the resulting string looks like a OpenVMS file
specification and the logical symbol is not a concealed device
name, the translation process is repeated.
If the logical symbol translates into an Rdb Transparent Gateway
access string (for example, /TYPE=VIDA/FILE=ACCESS_FILE/...),
Replication Option does no further translations. Even if
the VIDA name string contains logical symbol references,
these references are not translated into OpenVMS file
specifications. You can use a logical name in place of the
string to identify an Rdb Transparent Gateway database.
o Target database file logical name
If the target database name is a logical name, it is not
translated by Replication Option when it is stored in the
transfer definition.
o Copy process log file logical name
Replication Option translates the log file logical name in
the same way as source file logical names, with the following
exceptions:
o The log file specification is translated in RDO when the
DEFINE TRANSFER statement is executed.
o These log file names must be standard OpenVMS file
specifications. Node names or version numbers are not
allowed.
o Prologue and epilogue command procedure file logical names
Replication Option translates the prologue and epilogue file
logical names in the same way as the source file logical name,
with the following exceptions:
o The prologue and epilogue file specifications are
translated in RDO when the DEFINE TRANSFER statement is
executed.
o The log file names must be standard OpenVMS file
specifications. Node names and version numbers are
allowed. Replication Option expects node names in file
specifications to be from one to six characters long.
DECnet/OSI permits node names to be much longer than
this. In order to use Replication Option in a DECnet/OSI
environment, you must define and use short synonyms for
the long node names. Node name synonyms can be registered
either in a local or distributed name service database. For
details on establishing node name synonyms, refer to the
documentation for DECnet/OSI.
Prior to Rdb/VMS Version 3.1, data values for text fields were
sorted in ascending or descending order based on the ASCII
character set. With Rdb/VMS Version 3.1 and higher (and Oracle Rdb
Version 5.0 and higher), you can create databases that specify
different sort sequences on a field-by-field basis. You can
specify the default for the database as a whole. Replication Option
has not enhanced transfer definitions to handle collation
sequences in any way. In addition, target databases created by
Replication Option do not have the collation sequence attributes
defined. Sorting in a target database remains ASCII-based.
Currently, there is no way that users can transfer default
collation sequences for fields or databases.
In an extraction transfer, you can change table definitions
in the source database or definitions of columns on which the
transferred tables are based. However, those changes are not
reflected in the transfer definition.
In replication transfers, you can make such changes until the
initial transfer begins. Thereafter, any attempts to change
or delete definitions for tables or columns in the replication
transfer are not allowed, with the exception of the following
four column attributes; these attributes can be modified even
after the initial transfer begins:
o Edit string
o Default value for DATATRIEVE
o Query name for DATATRIEVE
o Query header
However, note that if you do change the attributes listed in a
source column, a comparable change is not made automatically to
the target database column. If you want that to happen, you must
make the change in both the source and the target databases.
In both extraction and replication transfers, if you make changes
that cause the source tables or columns to be incompatible
with the transfer definitions, Replication Option detects these
differences at the time of transfer execution. The transfer
fails, the transfer status reflects the failure, and the transfer
is suspended.
However, with extractions or initial replications, the copy
process does not detect changes to the data type of a field.
For example, you can change a field from the data type CHAR to
the data type INTEGER without causing a failure.
3 – Examples
Example 1
The following example defines a transfer, NH_EMPLOYEES, that
creates an extraction database. The transfer definition selects
New Hampshire employees' address records for transfer to the
remote node.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER NH_EMPLOYEES EXTRACTION
cont> DESCRIPTION IS /* Employees who live in New Hampshire */
cont> TO NODE1::DISK1:[ADAMS]NH_EMP
cont> MOVE RELATION E IN EMPLOYEES WITH E.STATE = "NH"
cont> SELECT FIELDS E.EMPLOYEE_ID,
cont> E.LAST_NAME,
cont> E.FIRST_NAME,
cont> E.MIDDLE_INITIAL,
cont> E.ADDRESS_DATA_1,
cont> E.ADDRESS_DATA_2,
cont> E.CITY,
cont> E.STATE,
cont> E.POSTAL_CODE
cont> LOG IS NH_EMPLOYEES.LOG
cont> END.
Example 2
This example shows an extraction from a remote source database to
a local target database. The DEFINE TRANSFER statement specifies
the transfer of all personnel records to the target node.
RDO> INVOKE DATABASE FILENAME NODE1::DISK1:[DIR1]PERSONNEL
RDO> DEFINE TRANSFER PERS_EXAMP EXTRACTION
cont> DESCRIPTION IS /* Extraction of personnel records*/
cont> TO [LEARNER.PERS]PERS_COPY
cont> MOVE RELATIONS ALL
cont> LOG IS [LEARNER.PERS]PERS_EXAMP.LOG
cont> END.
Example 3
This example shows an extraction transfer from a remote source
to a remote target database. The log file, PERS_EXAMP.LOG, is
located on the source node.
RDO> INVOKE DATABASE FILENAME NODE1::DISK1:[DIR1]PERSONNEL
RDO> DEFINE TRANSFER PERS_EXAMP EXTRACTION
cont> DESCRIPTION IS /* Extraction of personnel records*/
cont> TO NODE2::DISK2:[PROTO]PERS_TARGET
cont> MOVE RELATIONS ALL
cont> LOG IS PERS_EXAMP.LOG
cont> END.
Example 4
This example of a replication transfer definition sends the
entire colleges relation and the entire degrees relation to the
target database. The replication database can be accessed for
information about employees' college and degree histories. The
transfer definition includes some database parameters for the
target database.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER COLLEGE_INFO REPLICATION
cont> DESCRIPTION IS /* Info about employees' colleges only */
cont> TO NODE1::DISK1:[BURTON]EMP_COLLEGE
cont> NUMBER OF USERS IS 25
cont> SNAPSHOT ALLOCATION IS 150 PAGES
cont> MOVE RELATION C IN COLLEGES
cont> SELECT FIELDS ALL;
cont> MOVE RELATION D IN DEGREES
cont> SELECT FIELDS ALL
cont> LOG IS COLLEGE_INFO.LOG
cont> END.
Example 5
This replication transfer specifies three fields from the CREDIT_
CARDS source database for transfer to the target database. The
fields are CARD_NUM, EXPIRATION_DATE, and VALID. Only invalid
credit card records are selected for the transfer.
RDO> DEFINE TRANSFER BAD_CARDS REPLICATION
cont> DESCRIPTION IS /* Invalid credit cards */
cont> TO NODE1::DISK1:[CREDIT]BAD_CARDS
cont> MOVE RELATION C IN CARDS WITH C.VALID = "N"
cont> SELECT FIELDS C.CARD_NUM,
cont> C.EXPIRATION_DATE,
cont> C.VALID
cont> LOG IS BAD_CARDS.LOG
cont> END.
Example 6
The following example defines a replication transfer that sends
the entire EMPLOYEES, JOB_HISTORY, SALARY_HISTORY, DEPARTMENTS,
and JOBS relations. The definition also selects three views for
transfer: CURRENT_INFO, CURRENT_JOB, and CURRENT_SALARY.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER NH_PERSONNEL REPLICATION
cont> TO NODE1::DISK1:[DBADMIN]NHP.RDB
cont> MOVE RELATION E IN EMPLOYEES SELECT FIELDS ALL;
cont> MOVE RELATION JH IN JOB_HISTORY SELECT FIELDS ALL;
cont> MOVE RELATION SH IN SALARY_HISTORY SELECT FIELDS ALL;
cont> MOVE RELATION D IN DEPARTMENTS SELECT FIELDS ALL;
cont> MOVE RELATION J IN JOBS SELECT FIELDS ALL
cont> MOVE VIEWS CURRENT_INFO, CURRENT_JOB, CURRENT_SALARY
cont> LOG FILE IS DISK1:[DBADMIN]NHP.LOG
cont> END.
Example 7
The following example moves the CURRENT_JOB view defined in the
source database as a CROSS of the EMPLOYEES relation and the JOB_
HISTORY relation. You can achieve the effect of a CROSS clause
by transferring a view that is a CROSS in the source database. On
the target database, the records selected by the view are created
as a relation.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER CJOB EXTRACTION
cont> TO NODE1::DISK1:[RAMESH]JOB_DB
cont> MOVE RELATION C IN CURRENT_JOB WITH C.JOB_CODE = "SEII"
cont> SELECT FIELDS C.LAST_NAME, C.FIRST_NAME, C.ADDRESS
cont> LOG FILE IS CJOB.LOG
cont> END TRANSFER.
Example 8
The following example shows an extraction rollup transfer that
invokes several source databases: PERSONNEL, WORKERS, and STAFF.
The transfer selects fields in the EMPLOYEES relations from the
three databases identified by the database handles DB1, DB2, and
DB3 and located on three different nodes and in the JOBS relation
from DB1. Then the transfer moves these relations to a single
target database, LOCAL_DB.
RDO> INVOKE DATABASE DB1=FILENAME "NODE1::DISK1:[DIR1]PERSONNEL"
RDO> INVOKE DATABASE DB2=FILENAME "NODE2::DISK2:[DIR2]WORKERS"
RDO> INVOKE DATABASE DB3=FILENAME "NODE3::DISK3:[DIR1]STAFF"
RDO> DEFINE TRANSFER LABOR EXTRACTION ROLLUP
cont> TO NODE4::DISK4:[DIR4]LOCAL_DB
cont> MOVE RELATION E IN DB1.EMPLOYEES WITH E.EMP_CODE= "A+"
cont> INTO RELATION EXEMPT_EMPLOYEES
cont> SELECT FIELDS E.EMP.ID,E.SALARY,E.JOB_CODE;
cont> MOVE RELATION E IN DB2.EMPLOYEES WITH E.EMP_CODE= "A+"
cont> INTO RELATION EXEMPT_EMPLOYEES
cont> SELECT FIELDS E.EMP_ID,E.SALARY,E.JOB_CODE;
cont> MOVE RELATION E IN DB3.EMPLOYEES WITH E.EMP_CODE= "A+"
cont> INTO RELATION EXEMPT_EMPLOYEES
cont> SELECT FIELDS E.EMP.ID,E.SALARY,E.JOB_CODE;
cont> MOVE RELATION J IN DB1.JOBS WITH J.JOB_CODE= "J17"
cont> INTO RELATION ENTRY_JOBS
cont> SELECT FIELDS J.JOB_NAME,J.JOB_CODE
cont> LOG FILE IS DISK4:[DIR4]LOCAL.LOG
cont> END.
Example 9
The following EMPLOYEES transfer creates an extraction database.
The transfer selects records using a first-clause, with-clause,
reduce-clause, and sort-clause.
RDO> INVOKE DATABASE FILENAME PERSONNEL
RDO> DEFINE TRANSFER EMPLOYEES EXTRACTION
cont> TO NODE1::DISK1:[NELSON]EMPLOYEES_INFO
cont> MOVE RELATION FIRST 10 E IN EMPLOYEES
cont> WITH E.CITY = "BOSTON"
cont> REDUCED TO E.LAST_NAME, E.FIRST_NAME, E.ADDRESS
cont> SORTED BY DESCENDING E.LAST_NAME
cont> SELECT FIELDS E.LAST_NAME, E.FIRST_NAME, E.ADDRESS
cont> LOG FILE IS DISK1:[NELSON]EMPLOYEES.LOG
cont> END TRANSFER.
Example 10
The following extraction transfer includes two command files.
The prologue command procedure establishes a connection to a
remote node, and the epilogue command procedure terminates the
connection. This example shows how to specify the prologue file
and epilogue file; it does not show the command procedures.
RDO> INVOKE DATABASE FILENAME NODE1::DISK1:[DBADMIN.PERS]PERSONNEL
RDO> DEFINE TRANSFER PERS_SAMPLE EXTRACTION
cont> TO PERS_COPY
cont> MOVE RELATIONS ALL
cont> PROLOGUE FILE IS DIALUP.COM
cont> EPILOGUE FILE IS HANGUP.COM
cont> LOG IS PERS_SAMPLE.LOG
cont> END.