MDEV-37905: UNCACHEABLE_RAND inconsistently set on unions #4385
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DaveGosselin-MariaDB
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Updated to include a new test case that would crash without this fix in place. Adds a loop and assertion to check that if any SELECT is marked as UNCACHEABLE_RAND, then the corresponding union should be likewise marked. This loop and assertion only execute in builds where DBUG_ASSERT is available. |
spetrunia
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sql/sql_lex.cc
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| bool has_rand= false; | ||
| for (SELECT_LEX *sl= un->first_select(); sl && !has_rand; | ||
| sl= sl->next_select()) | ||
| has_rand= sl->uncacheable & UNCACHEABLE_RAND; |
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IIRC some compilers will give a warning for this, need to have
has_rand= (sl->uncacheable & UNCACHEABLE_RAND);
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Thank you, will update this before pushing.
We need to ensure that all the unions are marked as UNCACHEABLE_RAND in cases like: select * from t1 where 1 in (select 1 union select 2 union select RAND());
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We need to ensure that all the unions are marked as UNCACHEABLE_RAND in cases like: