[MDEV-19154] Cost based choice between materialization and merge of mergeable derived tables / views / CTE Created: 2019-04-03 Updated: 2019-10-22 |
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| Status: | Open |
| Project: | MariaDB Server |
| Component/s: | None |
| Fix Version/s: | None |
| Type: | Task | Priority: | Major |
| Reporter: | Igor Babaev | Assignee: | Igor Babaev |
| Resolution: | Unresolved | Votes: | 0 |
| Labels: | None | ||
| Description |
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Currently mergeable derived table / views / CTE are merged if there are not too many joined tables in select. The decision to merge or to materialize must be cost based. |