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Merge branch '10.6' into 10.7

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This commit is contained in:
Sergei Golubchik
2022-02-10 21:16:50 +01:00
parent 9bd7e526e7 e3894f5d39
commit 65f602310c
26 changed files with 5576 additions and 39 deletions
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16
sql/sql_lex.cc
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@ -4965,7 +4965,21 @@ bool st_select_lex::optimize_unflattened_subqueries(bool const_only)
}
if (empty_union_result)
subquery_predicate->no_rows_in_result();
if (!is_correlated_unit)
if (is_correlated_unit)
{
/*
Some parts of UNION are not correlated. This means we will need to
re-execute the whole UNION every time. Mark all parts of the UNION
as correlated so that they are prepared to be executed multiple
times (if we don't do that, some part of the UNION may free its
execution data at the end of first execution and crash on the second
execution)
*/
for (SELECT_LEX *sl= un->first_select(); sl; sl= sl->next_select())
sl->uncacheable |= UNCACHEABLE_DEPENDENT;
}
else
un->uncacheable&= ~UNCACHEABLE_DEPENDENT;
subquery_predicate->is_correlated= is_correlated_unit;
}