File: select_debug.result

package info (click to toggle)
mariadb-10.0 10.0.30-0%2Bdeb8u2
  • links: PTS, VCS
  • area: main
  • in suites: jessie
  • size: 474,048 kB
  • ctags: 183,740
  • sloc: cpp: 1,391,728; ansic: 831,813; perl: 59,717; sh: 36,566; pascal: 32,281; yacc: 14,921; xml: 5,257; sql: 4,660; cs: 4,647; makefile: 4,555; ruby: 4,465; python: 2,292; lex: 1,427; java: 941; asm: 295; awk: 54; php: 22; sed: 16
file content (18 lines) | stat: -rw-r--r-- 610 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
#
# Bug #725050: print keyuse info when  hash join is used 
#
create table t1 (a int, b int);
insert into t1 values (2,2), (1,1);
create table t2 (a int);
insert into t2 values (2), (3);
set session join_cache_level=3;
set @@debug_dbug= 'd,opt';
explain select t1.b from t1,t2 where t1.b=t2.a;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
1	SIMPLE	t2	hash_ALL	NULL	#hash#$hj	5	test.t1.b	2	Using where; Using join buffer (flat, BNLH join)
select t1.b from t1,t2 where t1.b=t2.a;
b
2
set session join_cache_level=default;
drop table t1,t2;