[EMPIREDB-212] MySQL Nested Union bad syntax

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: empire-db-2.4.2
• Fix Version/s: empire-db-2.4.4
• Component/s: CodeGenerator
• Labels: mysql nested union
• Assignee: Rainer Döbele
• Reporter: Ivan Arrizabalaga Getino
• Created: 15/Sep/14 09:28
• Updated: 01/Oct/14 11:27
• Resolved: 01/Oct/14 11:27

Description

If you try to create a union with several tables:

select 1 UNION select 2 UNION select 3

the DBDatabaseDriverMySQL driver generates:

( (select 1) UNION (select 2)) UNION (select 3)

and MySQL does NOT support nested UNIONs.

If could solved by changing the anonymous class in DBDatabaseDriverMySQL.createCombinedCommand but it should be done by default.