spark-instrumented-optimizer/sql/core
Josh Rosen 15539e54c2 [SPARK-17355] Workaround for HIVE-14684 / HiveResultSetMetaData.isSigned exception
## What changes were proposed in this pull request?

Attempting to use Spark SQL's JDBC data source against the Hive ThriftServer results in a `java.sql.SQLException: Method` not supported exception from `org.apache.hive.jdbc.HiveResultSetMetaData.isSigned`. Here are two user reports of this issue:

- https://stackoverflow.com/questions/34067686/spark-1-5-1-not-working-with-hive-jdbc-1-2-0
- https://stackoverflow.com/questions/32195946/method-not-supported-in-spark

I have filed [HIVE-14684](https://issues.apache.org/jira/browse/HIVE-14684) to attempt to fix this in Hive by implementing the isSigned method, but in the meantime / for compatibility with older JDBC drivers I think we should add special-case error handling to work around this bug.

This patch updates `JDBCRDD`'s `ResultSetMetadata` to schema conversion to catch the "Method not supported" exception from Hive and return `isSigned = true`. I believe that this is safe because, as far as I know, Hive does not support unsigned numeric types.

## How was this patch tested?

Tested manually against a Spark Thrift Server.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #14911 from JoshRosen/hive-jdbc-workaround.
2016-09-01 16:45:26 -07:00
..
benchmarks [SPARK-15881] Update microbenchmark results for WideSchemaBenchmark 2016-06-11 15:26:08 -07:00
src [SPARK-17355] Workaround for HIVE-14684 / HiveResultSetMetaData.isSigned exception 2016-09-01 16:45:26 -07:00
pom.xml [SPARK-16535][BUILD] In pom.xml, remove groupId which is redundant definition and inherited from the parent 2016-07-19 11:59:46 +01:00