[OPENJPA-1376] @SequenceGenerator allocationSize incorrect implementation

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.1, 2.0.0-M3, 2.1.0
• Fix Version/s: 1.2.3, 1.3.0, 2.0.2, 2.1.2, 2.2.0
• Component/s: competitive, jdbc, performance
• Environment: All
• Assignee: Milosz Tylenda
• Reporter: Yves
• Created: 04/Nov/09 23:49
• Updated: 08/Nov/13 20:47
• Resolved: 13/Mar/11 09:57

Description

OpenJpa use allocationSize parameter on NativeJDBCSeq to set the sequence cache value.

But one "JSR 220: Enterprise JavaBeansTM,Version 3.0" , the allocationSize is : "The amount to increment by when allocating sequence
numbers from the sequence."

Allocating is used to limit the number of access to the sequence or table not to set the sequence cache value !

If allocationSize=50, the sequence need to be call one time on each 50 call on AbstractJDBCSeq.next().

1 call on AbstractJDBCSeq.next(). call the sequence or table
2 call : return previous value + 1;
3 call : return previous value + 2;
...
51 call :re-call the sequence
52 return previous value + 1
...

Issue Links

• is related to: OPENJPA-2450 Option to disable execution of ALTER SEQUENCE...INCREMENT BY statement for sequences.
• relates to: OPENJPA-2069 Natvie sequence problems uncovered after OPENJPA-1376
• relates to: OPENJPA-2196 Create Sequence Postgres 9.1