[CALCITE-1147] Allow multiple providers for the same kind of metadata

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.7.0
• Assignee: Julian Hyde
• Reporter: Wei Xue
• Created: 10/Mar/16 15:11
• Updated: 24/Mar/16 19:11
• Resolved: 17/Mar/16 22:12

Description

I am getting exceptions caused by CALCITE-604.

The first exception I got while using PhoenixMetadataProvider was: "java.lang.IllegalArgumentException: duplicate key" in ChainedMetadataProvider.handlers(), which was caused by the use of ImmutableMap.Builder.
According to https://groups.google.com/forum/#!topic/sakai-kernel/Kj1WRBg9pi8, in such scenarios, we should use HashMap instead.

After fixing the above issue, I got NPE at ReflectiveRelMetadataProvider.java:278 if (RelNode.class.isAssignableFrom(relClass.getSuperclass())) {, for which I didn't know why it hadn't caused any trouble before. Since this logic wasn't really changed in CALCITE-604, I assume it went through the wrong code path.

Looks like we should add more test cases for custom metadata in Calcite.

Issue Links

• depends upon: CALCITE-604 Invoke metadata providers via a class generated at runtime, rather than reflection
• relates to: CALCITE-1169 Memory leak caused by CALCITE-604 and CALCITE-1147