[ORC-759] StructBatchReader should always skip processing on the rootReader

• Type: Sub-task
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.7.0
• Component/s: Java
• Assignee: Pavan Lanka
• Reporter: Pavan Lanka
• Created: 12/Mar/21 17:53
• Updated: 21/Sep/21 20:45
• Resolved: 24/Mar/21 17:20

Description

As of right now the processing in StructBatchReader is as follows:

• `nextBatch` method : Perform directly on the children with the assumption that the rootReader has no nulls.
• `seek`, `skipRows`, `startStripe` methods: Operate on the rootReader

Propose that the StructBatchReader be made consistently to operate on the children and never on the rootReader.

Issue Links

• depends upon: ORC-758 Avoid decompressing compressed streams if already decompressed
• links to: GitHub Pull Request #653