[HIVE-2171] Allow custom serdes to set field comments

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.7.0
• Fix Version/s: 0.8.0
• Hadoop Flags: Reviewed
• Assignee: Jakob Homan
• Reporter: Jakob Homan
• Created: 19/May/11 18:43
• Updated: 16/Dec/11 23:56
• Resolved: 12/Aug/11 19:29

Description

Currently, while serde implementations can set a field's name, they can't set its comment. These are set in the metastore utils to (from deserializer). For those serdes that can provide meaningful comments for a field, they should be propagated to the table description. These serde-provided comments could be prepended to "(from deserializer)" if others feel that's a meaningful distinction. This change involves updating StructField to support a (possibly null) comment field and then propagating this change out to the myriad places StructField is thrown around.