[HIVE-11344] HIVE-9845 makes HCatSplit.write modify the split so that PartInfo objects are unusable after it

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.0
• Fix Version/s: 1.2.2, 1.3.0, 2.0.0
• Assignee: Sushanth Sowmyan
• Reporter: Sushanth Sowmyan
• Created: 22/Jul/15 21:29
• Updated: 16/Feb/16 23:53
• Resolved: 27/Jul/15 16:30

Description

HIVE-9845 introduced a notion of compression for HCatSplits so that when serializing, it finds commonalities between PartInfo and TableInfo objects, and if the two are identical, it nulls out that field in PartInfo, thus making sure that when PartInfo is then serialized, info is not repeated.

This, however, has the side effect of making the PartInfo object unusable if HCatSplit.write has been called.

While this does not affect M/R directly, since they do not know about the PartInfo objects and once serialized, the HCatSplit object is recreated by deserializing on the backend, which does restore the split and its PartInfo objects, this does, however, affect framework users of HCat that try to mimic M/R and then use the PartInfo objects to instantiate distinct readers.

Thus, we need to make it so that PartInfo is still usable after HCatSplit.write is called.

Issue Links

• is related to: HIVE-11697 Add Unit Test to test serializability/deserializability of HCatSplits
• relates to: HIVE-9845 HCatSplit repeats information making input split data size huge