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Merge 10.1 into 10.2

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This commit is contained in:
Marko Mäkelä
2020-08-10 17:57:14 +03:00
parent 0460d42b94 7f67ef1485
commit 3b6dadb5eb
19 changed files with 412 additions and 410 deletions
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19
sql/sql_union.cc
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@ -514,6 +514,25 @@ bool st_select_lex_unit::prepare(THD *thd_arg, select_result *sel_result,
found_rows_for_union= first_sl->options & OPTION_FOUND_ROWS;
is_union_select= is_union() || fake_select_lex;
/*
If we are reading UNION output and the UNION is in the
IN/ANY/ALL/EXISTS subquery, then ORDER BY is redundant and hence should
be removed.
Example:
select ... col IN (select col2 FROM t1 union select col3 from t2 ORDER BY 1)
(as for ORDER BY ... LIMIT, it currently not supported inside
IN/ALL/ANY subqueries)
(For non-UNION this removal of ORDER BY clause is done in
check_and_do_in_subquery_rewrites())
*/
if (is_union() && item &&
(item->is_in_predicate() || item->is_exists_predicate()))
{
global_parameters()->order_list.first= NULL;
global_parameters()->order_list.elements= 0;
}
/* Global option */
if (is_union_select || is_recursive)