(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 – 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.
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.
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.
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.
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.