Enable predicate push-down optimization by default. #4846
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Collect all test failures and segfaults.
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@alexey-milovidov I don't see any differences in the PVS report, that you mentioned earlier in Telegram Chat. Can you point out what new errors/warnings were introduced in this PR? |
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| /// SELECT a, b FROM (SELECT 1 AS a) ANY LEFT JOIN (SELECT 1 AS a, 1 AS b WHERE b = 0) USING (a) WHERE b = 0 | ||
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| /// That leads to the empty result in the right subquery and changes the whole outcome to (1, 0) or (1, NULL). |
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👍 Are we going to move the entire predicate optimization onto the execution stack in the future ? and how do we do that ? Maybe I can get on with this work?
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Yes, we are going to do it after "Processors" will be ready #4914
And we will be happy to have your help!
There is no difference in PVS report for now. |
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00933_ttl_simple in tsan - TODO @alesapin |
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For changelog. Remove if this is non-significant change.
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Short description (up to few sentences):
Disable push-down to right table in left join, left table in right join, and both tables in full join.
Detailed description:
The current implementation of push-down has a bug in cases like:
SELECT a, b FROM (SELECT 1 AS a) ANY LEFT JOIN (SELECT 1 AS a, 1 AS b) USING (a) WHERE b = 0It can't be fixed on syntax level, so in the future we have to move this optimization deeper into execution stack.