From 15539e54c2650a164f09c072f8fae934bb0468c9 Mon Sep 17 00:00:00 2001 From: Josh Rosen Date: Thu, 1 Sep 2016 16:45:26 -0700 Subject: [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 Closes #14911 from JoshRosen/hive-jdbc-workaround. --- .../apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'sql/core') diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala index 8d9048ab82..9b5088fbfd 100644 --- a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala +++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala @@ -136,7 +136,16 @@ object JDBCRDD extends Logging { val typeName = rsmd.getColumnTypeName(i + 1) val fieldSize = rsmd.getPrecision(i + 1) val fieldScale = rsmd.getScale(i + 1) - val isSigned = rsmd.isSigned(i + 1) + val isSigned = { + try { + rsmd.isSigned(i + 1) + } catch { + // Workaround for HIVE-14684: + case e: SQLException if + e.getMessage == "Method not supported" && + rsmd.getClass.getName == "org.apache.hive.jdbc.HiveResultSetMetaData" => true + } + } val nullable = rsmd.isNullable(i + 1) != ResultSetMetaData.columnNoNulls val metadata = new MetadataBuilder() .putString("name", columnName) -- cgit v1.2.3