[HIVE-19750] Initialize NEXT_WRITE_ID. NWI_NEXT on converting an existing table to full acid

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 3.0.0
• Fix Version/s: 3.1.0
• Component/s: Transactions
• Assignee: Eugene Koifman
• Reporter: Eugene Koifman
• Created: 31/May/18 19:29
• Updated: 31/Jul/18 01:33
• Resolved: 08/Jun/18 18:04

Description

Need to set this to a reasonably high value the the table.
This will reserve a range of write IDs that will be treated by the system as committed.
This is needed so that we can assign unique ROW__IDs to each row in files that already exist in the table. For example, if the value is initialized to the number of files currently in the table, we can think of each file as written by a separate transaction and thus a free to assign bucketProperty (BucketCodec) of ROW_ID in whichever way is convenient.
it's guaranteed that all rows get unique ROW_IDs this way.

Issue Links

• relates to: HIVE-18774 ACID: Use the _copy_N files copyNumber as the implicit statement-id
• relates to: HIVE-19749 Acid V1 to V2 upgrade