1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
# include/expect_qep.inc
#
# SUMMARY
#
# Designed to be used together with include/check_qep.inc
#
# $query should be assigned a select statement using
# straight_join to force the tables to be joined in most
# optimal order.
#
# expect_qep.inc will then store the estimated 'Last_query_cost'
# and total # 'Handler_read%' for this straight_joined query.
#
# We should then assign a non-straight_join'ed version of
# the same query to $query and execute it using
# 'include/check_qep.inc'. Its estimated cost and
# #handler_reads will then be verified against the
# previous straight_joined query.
#
# USAGE
#
# let $query= <select straight_join optimal statement>;
# --source include/expect_qep.inc
# let $query= <select statement>;
# --source include/check_qep.inc
#
# EXAMPLE
# t/greedy_optimizer.test
#
flush status;
eval EXPLAIN $query;
eval $query;
let $best_cost=
query_get_value(SHOW STATUS LIKE 'Last_query_cost', Value, 1);
let $best_reads=
`select sum(variable_value)
from information_schema.session_status
where VARIABLE_NAME like 'Handler_read%'`;
#echo Expect, cost: $best_cost, Handler_reads: $best_reads;
|
