[OPENJPA-710] Unordered collection field adds ORDER BY clause

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.1.0, 1.2.0, 1.2.1, 1.3.0
• Fix Version/s: 1.0.4, 1.2.0, 1.2.1, 1.3.0
• Component/s: kernel
• Assignee: Pinaki Poddar
• Reporter: Pinaki Poddar
• Created: 02/Sep/08 21:14
• Updated: 21/Sep/16 14:21
• Resolved: 03/Sep/08 00:29

Description

An ORDER BY clause is added while selecting even for collection-valued fields that do not require ordering.

For example, consider a typical Parent-Child model with bi-directional relationship where Parent.children is declared and/or initialized as a Set rather than a List will result in the following SQL
"SELECT t0.id, t0.name, t1.id FROM PARENT t0 LEFT OUTER JOIN CHILD t1 ON t0.id = t1.PARENT_ID ORDER BY t1.PARENT_ID"
corresponding to JPQL "select p from Parent p left join fetch p.children".

Is ORDER BY clause necessary in this context? I
t also adds an extra performance overhead on the SQL query execution for a fairly frequent usage pattern.