[HBASE-899] Support for specifying a timestamp and numVersions on a per-column basis

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Assignee: Unassigned
• Reporter: Dogacan Guney
• Created: 23/Sep/08 23:00
• Updated: 11/Jun/22 20:16
• Resolved: 16/Jul/14 18:08

Description

This is just an idea and it may be better to wait after the planned API changes. But I think it would be useful to support fetching different timestamps and versions for different columns.

Example:

If a row has 2 columns, "col1:" and "col2:" I want to be able to ask for (during scan or read time, doesn't matter) 2 versions of "col1:" (maybe even between timestamps t1 and t2) but only 1 version of "col2:". This would be especially handy if during an MR job you have to read 2 versions of a small column, but do not want the overhead of reading 2 versions of every other column too....

(Also, the mechanism is already there. I mean, making the changes to support a per-column timestamp/numVersions is ridiculously easy

Issue Links

• is blocked by: HBASE-861 get with timestamp will return a value if there is a version with an earlier timestamp
• is blocked by: HBASE-847 new API: HTable.getRow with numVersion specified
• is blocked by: HBASE-52 [hbase] Add a means of scanning over all versions
• is part of: HBASE-1249 Rearchitecting of server, client, API, key format, etc for 0.20