* Bug #20792: Incorrect results from aggregate subquery

When processing aggregate functions all tables values are reset
to NULLs at the end of each group. 
When doing that if there are no rows found for a group
the const tables must not be reset as they are not recalculated 
by do_select()/sub_select() for each group.
This commit is contained in:
gkodinov/kgeorge@macbook.gmz 2006-07-26 19:19:30 +03:00
parent a8d230c672
commit 565d495997
3 changed files with 38 additions and 2 deletions

View File

@ -130,3 +130,15 @@ id select_type table type possible_keys key key_len ref rows Extra
5 DEPENDENT SUBQUERY t3 unique_subquery PRIMARY,FFOLDERID_IDX PRIMARY 32 func 1 Using index; Using where
6 DEPENDENT SUBQUERY t3 unique_subquery PRIMARY,FFOLDERID_IDX,CMFLDRPARNT_IDX PRIMARY 32 func 1 Using index; Using where
drop table t1, t2, t3, t4;
CREATE TABLE t1 (a int(10) , PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t1 VALUES (1),(2);
CREATE TABLE t2 (a int(10), PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t2 VALUES (1);
CREATE TABLE t3 (a int(10), b int(10), c int(10),
PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t3 VALUES (1,2,1);
SELECT t1.* FROM t1 WHERE (SELECT COUNT(*) FROM t3,t2 WHERE t3.c=t2.a
and t2.a='1' AND t1.a=t3.b) > 0;
a
2
DROP TABLE t1,t2,t3;

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@ -150,3 +150,21 @@ EXPLAIN SELECT t2.*, t4.DOCTYPENAME, t1.CONTENTSIZE,t1.MIMETYPE FROM t2 INNER JO
drop table t1, t2, t3, t4;
# End of 4.1 tests
#
# Bug #20792: Incorrect results from aggregate subquery
#
CREATE TABLE t1 (a int(10) , PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t1 VALUES (1),(2);
CREATE TABLE t2 (a int(10), PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t2 VALUES (1);
CREATE TABLE t3 (a int(10), b int(10), c int(10),
PRIMARY KEY (a)) Engine=InnoDB;
INSERT INTO t3 VALUES (1,2,1);
SELECT t1.* FROM t1 WHERE (SELECT COUNT(*) FROM t3,t2 WHERE t3.c=t2.a
and t2.a='1' AND t1.a=t3.b) > 0;
DROP TABLE t1,t2,t3;

View File

@ -4452,10 +4452,16 @@ return_zero_rows(JOIN *join, select_result *result,TABLE_LIST *tables,
DBUG_RETURN(0);
}
/*
used only in JOIN::clear
*/
static void clear_tables(JOIN *join)
{
for (uint i=0 ; i < join->tables ; i++)
/*
must clear only the non-const tables, as const tables
are not re-calculated.
*/
for (uint i=join->const_tables ; i < join->tables ; i++)
mark_as_null_row(join->table[i]); // All fields are NULL
}