[IGNITE-6843] SQL: Optionally do not use WAL when executing CREATE INDEX

• Type: Task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.3
• Component/s: sql
• Labels: iep-19 performance
• Assignee: Unassigned
• Reporter: Vladimir Ozerov
• Created: 08/Nov/17 14:09
• Updated: 25/Apr/18 14:16

Description

Inspired by Oracle NOLOGGING option [1].

When an index is being created through CREATE INDEX command, every single index update is written to WAL. Let's introduce special mode where updates are not written to WAL:
1) Index updates during an index_create operation are not written to WAL
2) When the index is ready, force a checkpoint and wait for it to happen
3) Purge index data if node crashed before checkpoint

Alternatively, we may even not trigger a checkpoint, hoping that that node will not crash before the nearest checkpoint is finished. If node crashed during this time window, the index should be marked as "invalid", and not used for queries. Then the user should either re-create or rebuild it.

[1] https://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_5010.htm#i2182589