1
0
mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00

Bug #30715: Assertion failed: item_field->field->real_maybe_null(),

file .\opt_sum.cc, line
The optimizer pre-calculates the MIN/MAX values for queries like
 SELECT MIN(kp_k) WHERE kp_1 = const AND ... AND kp_k-1 = const
when there is a key over kp_1...kp_k
In doing so it was not checking correctly nullability and 
there was a superfluous assert(). 
Fixed by making sure that the field can be null before checking and
taking out the wrong assert().
.
Introduced a correct check for nullability 
The MIN(field) can return NULL when all the row values in the group
are NULL-able or if there were no rows.
Fixed the assertion to reflect the case when there are no rows.


mysql-test/r/func_group.result:
  Bug #30715: test case
mysql-test/t/func_group.test:
  Bug #30715: test case
sql/opt_sum.cc:
  Bug #30715: correct nullability check for MIN/MAX pre-calculation over index.
This commit is contained in:
unknown
2007-10-24 11:15:08 +03:00
parent 62a7e160bc
commit e2433cbcaa
3 changed files with 19 additions and 5 deletions

View File

@ -1387,4 +1387,9 @@ SELECT 1 FROM t1 GROUP BY (SELECT SLEEP(0) FROM t1 ORDER BY AVG(DISTINCT a) );
1
1
DROP TABLE t1;
CREATE TABLE t1 (a int, b date NOT NULL, KEY k1 (a,b));
SELECT MIN(b) FROM t1 WHERE a=1 AND b>'2007-08-01';
MIN(b)
NULL
DROP TABLE t1;
End of 5.0 tests