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Milosz Tylenda commented on OPENJPA-736: ---------------------------------------- Points 1, 2 and 3 applied to trunk. > Combine insert and select SQL together for generated Id > strategy=GenerationType.IDENTITY > ----------------------------------------------------------------------------------------- > > Key: OPENJPA-736 > URL: https://issues.apache.org/jira/browse/OPENJPA-736 > Project: OpenJPA > Issue Type: Improvement > Affects Versions: 1.3.0 > Reporter: Fay Wang > Assignee: Milosz Tylenda > Fix For: 1.3.0 > > Attachments: openjpa-736.patch, supportsGetGeneratedKeys.patch > > > Currently if the strategy of the generated id is GenerationType.IDENTITY, > when an entity object is created, openjpa will generate two SQL statements. > The following is an example running on DB2: > (1) INSERT INTO EntityA (col1, col2, col3, version) VALUES (?, ?, ?, ?) > [params=(int) 1, (int) 1, (int) 1, (int) 1] > (2) SELECT IDENTITY_VAL_LOCAL() FROM SYSIBM.SYSDUMMY1 > A performance improvement is to take advantage of the "select from final > table" feature in DB2 to combine the insert and select statement into a > single SQL statement as shown below: > SELECT id FROM FINAL TABLE (INSERT INTO EntityA (col1, col2, col3, version) > VALUES (?, ?, ?, ?) ) -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.