[SPARK-21617] ALTER TABLE...ADD COLUMNS broken in Hive 2.1 for DS tables

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.2.0
• Fix Version/s: 2.2.1, 2.3.0
• Component/s: SQL
• Assignee: Marcelo Masiero Vanzin
• Reporter: Marcelo Masiero Vanzin
• Created: 02/Aug/17 22:09
• Updated: 01/Sep/17 18:01
• Resolved: 21/Aug/17 22:10

Description

When you have a data source table and you run a "ALTER TABLE...ADD COLUMNS" query, Spark will save invalid metadata to the Hive metastore.

Namely, it will overwrite the table's schema with the data frame's schema; that is not desired for data source tables (where the schema is stored in a table property instead).

Moreover, if you use a newer metastore client where METASTORE_DISALLOW_INCOMPATIBLE_COL_TYPE_CHANGES is on by default, you actually get an exception:

InvalidOperationException(message:The following columns have types incompatible with the existing columns in their respective positions :
c1)
	at org.apache.hadoop.hive.metastore.MetaStoreUtils.throwExceptionIfIncompatibleColTypeChange(MetaStoreUtils.java:615)
	at org.apache.hadoop.hive.metastore.HiveAlterHandler.alterTable(HiveAlterHandler.java:133)
	at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.alter_table_core(HiveMetaStore.java:3704)
	at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.alter_table_with_environment_context(HiveMetaStore.java:3675)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.hadoop.hive.metastore.RetryingHMSHandler.invokeInternal(RetryingHMSHandler.java:140)
	at org.apache.hadoop.hive.metastore.RetryingHMSHandler.invoke(RetryingHMSHandler.java:99)
	at com.sun.proxy.$Proxy26.alter_table_with_environment_context(Unknown Source)
	at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.alter_table_with_environmentContext(HiveMetaStoreClient.java:402)
	at org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient.alter_table_with_environmentContext(SessionHiveMetaStoreClient.java:309)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.invoke(RetryingMetaStoreClient.java:154)
	at com.sun.proxy.$Proxy27.alter_table_with_environmentContext(Unknown Source)
	at org.apache.hadoop.hive.ql.metadata.Hive.alterTable(Hive.java:601)

That exception is handled by Spark in an odd way (see code in HiveExternalCatalog.scala) which still stores invalid metadata.

Issue Links

• links to: [Github] Pull Request #18849 (vanzin)