[DERBY-4031] If NO_GENERATED_KEYS is specified, Statement.getGeneratedKeys should return an empty ResultSet, not null

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 10.3.3.0, 10.4.2.0, 10.5.1.1
• Component/s: JDBC
• Labels: derby_triage10_5_2
• Urgency: Normal
• Issue & fix info: Release Note Needed
• Bug behavior facts: Deviation from standard
• Assignee: Unassigned
• Reporter: Katherine Marsden
• Created: 27/Jan/09 16:59
• Updated: 15/Feb/11 21:08

Description

Currently Derby returns null from Statement.getGeneratedKeys() if the statement is prepared or executed with Statement.NO_GENERATED_KEYS. The javadoc says:

If this Statement object did not generate any keys, an empty ResultSet object is returned.

so we should return an empty ResultSet for this case. It is not entirely clear what the structure of the ResultSet and ResultSetMetaData should be. I tend to think the following:

getConcurrency() - inherit from the parent statement
getStatement() - null

ResultSetMetaData
getColumnCount - 0

an alternative would be to have the ResultSetMetaData match the signature of Identity_Val_local() but I think to return 0 columns makes more sense.

Issue Links

• relates to: DERBY-4015 Regression in Statement.getGeneratedKeys()