apache/spark — pull request #1294 by liancheng (2014-07-03 20:52:12+00:00)
Title: Don't throw TreeNodeException in `execution.ExplainCommand`

This is a fix for the problem revealed by PR #1265.

Currently `HiveComparisonSuite` ignores output of `ExplainCommand` since Catalyst query plan is quite different from Hive query plan. But exceptions throw from `CheckResolution` still breaks test cases. This PR catches any `TreeNodeException` and reports it as part of the query explanation.

After merging this PR, PR #1265 can also be merged safely.