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Lukas Eder commented on DERBY-6983: ----------------------------------- I see, thanks a lot for the clarification. Indeed, it did not occur to me that your comment could have been intended in this way. In any case, no offense at all! > Support SELECT * for IN predicate subqueries when it is "obvious" that the > asterisk expands to exactly one column > ----------------------------------------------------------------------------------------------------------------- > > Key: DERBY-6983 > URL: https://issues.apache.org/jira/browse/DERBY-6983 > Project: Derby > Issue Type: Improvement > Components: SQL > Affects Versions: 10.14.1.0 > Reporter: Lukas Eder > Priority: Major > > The following query is not allowed in Derby: > {code:java} > SELECT * > FROM sys.systables > WHERE tablename IN ( > SELECT * > FROM ( > SELECT 'SYSTABLES' t > FROM sysibm.sysdummy1 > ) t > ){code} > The error I'm getting is: > {code:java} > 'SELECT *' only allowed in EXISTS and NOT EXISTS subqueries.{code} > In this case, it is "obvious" that the asterisk (also a qualified asterisk: > t.*) expands to exactly one column and the query should be perfectly fine. > I'm not aware of any other databases with such a restriction. > -- This message was sent by Atlassian JIRA (v7.6.3#76005)