mirror of
https://github.com/MariaDB/server.git
synced 2026-04-25 01:35:31 +02:00
21b1b5f040
Applied the fix for bug #47217 from the mysql-6.0 codebase. The patch adds not null predicates generated for the left parts of the equality predicates used for ref accesses. This is done for such predicates both in where conditions and on conditions. For the where conditions the not null predicates were generated but in 5.0/5.1 they actually never were used due to some lame merge from 4.1 to 5.0. The fix for bug #47217 made these predicates to be used in the condition pushed to the tables. Yet only this patch generates not null predicates for equality predicated from on conditions of outer joins. This patch introduces a performance regression that can be observed on a test case from null_key.test. The regression will disappear after the fix for bug #57024 from mariadb-5.1 is pulled into mariadb-5.3. The patch contains many changes in the outputs of the EXPLAIN commands since generated not null predicates are considered as parts of the conditions pushed to join tables and may add 'Usingwhere' in some rows of EXPLAINs where there used to be no such comments.
657 lines
40 KiB
Text
657 lines
40 KiB
Text
drop table if exists t1,t2,t3,t4,t5,t6,t7;
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create table t1 (
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c11 integer,c12 integer,c13 integer,c14 integer,c15 integer,c16 integer,
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primary key (c11)
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);
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create table t2 (
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c21 integer,c22 integer,c23 integer,c24 integer,c25 integer,c26 integer
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);
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create table t3 (
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c31 integer,c32 integer,c33 integer,c34 integer,c35 integer,c36 integer,
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primary key (c31)
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);
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create table t4 (
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c41 integer,c42 integer,c43 integer,c44 integer,c45 integer,c46 integer
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);
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create table t5 (
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c51 integer,c52 integer,c53 integer,c54 integer,c55 integer,c56 integer,
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primary key (c51)
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);
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create table t6 (
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c61 integer,c62 integer,c63 integer,c64 integer,c65 integer,c66 integer
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);
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create table t7 (
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c71 integer,c72 integer,c73 integer,c74 integer,c75 integer,c76 integer,
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primary key (c71)
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);
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insert into t1 values (1,2,3,4,5,6);
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insert into t1 values (2,2,3,4,5,6);
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insert into t1 values (3,2,3,4,5,6);
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insert into t2 values (1,2,3,4,5,6);
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insert into t2 values (2,2,3,4,5,6);
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insert into t2 values (3,2,3,4,5,6);
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insert into t2 values (4,2,3,4,5,6);
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insert into t2 values (5,2,3,4,5,6);
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insert into t2 values (6,2,3,4,5,6);
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insert into t3 values (1,2,3,4,5,6);
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insert into t3 values (2,2,3,4,5,6);
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insert into t3 values (3,2,3,4,5,6);
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insert into t3 values (4,2,3,4,5,6);
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insert into t3 values (5,2,3,4,5,6);
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insert into t3 values (6,2,3,4,5,6);
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insert into t3 values (7,2,3,4,5,6);
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insert into t3 values (8,2,3,4,5,6);
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insert into t3 values (9,2,3,4,5,6);
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insert into t4 values (1,2,3,4,5,6);
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insert into t4 values (2,2,3,4,5,6);
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insert into t4 values (3,2,3,4,5,6);
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insert into t4 values (4,2,3,4,5,6);
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insert into t4 values (5,2,3,4,5,6);
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insert into t4 values (6,2,3,4,5,6);
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insert into t4 values (7,2,3,4,5,6);
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insert into t4 values (8,2,3,4,5,6);
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insert into t4 values (9,2,3,4,5,6);
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insert into t4 values (10,2,3,4,5,6);
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insert into t4 values (11,2,3,4,5,6);
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insert into t4 values (12,2,3,4,5,6);
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insert into t5 values (1,2,3,4,5,6);
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insert into t5 values (2,2,3,4,5,6);
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insert into t5 values (3,2,3,4,5,6);
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insert into t5 values (4,2,3,4,5,6);
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insert into t5 values (5,2,3,4,5,6);
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insert into t5 values (6,2,3,4,5,6);
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insert into t5 values (7,2,3,4,5,6);
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insert into t5 values (8,2,3,4,5,6);
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insert into t5 values (9,2,3,4,5,6);
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insert into t5 values (10,2,3,4,5,6);
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insert into t5 values (11,2,3,4,5,6);
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insert into t5 values (12,2,3,4,5,6);
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insert into t5 values (13,2,3,4,5,6);
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insert into t5 values (14,2,3,4,5,6);
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insert into t5 values (15,2,3,4,5,6);
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insert into t6 values (1,2,3,4,5,6);
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insert into t6 values (2,2,3,4,5,6);
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insert into t6 values (3,2,3,4,5,6);
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insert into t6 values (4,2,3,4,5,6);
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insert into t6 values (5,2,3,4,5,6);
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insert into t6 values (6,2,3,4,5,6);
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insert into t6 values (7,2,3,4,5,6);
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insert into t6 values (8,2,3,4,5,6);
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insert into t6 values (9,2,3,4,5,6);
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insert into t6 values (10,2,3,4,5,6);
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insert into t6 values (11,2,3,4,5,6);
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insert into t6 values (12,2,3,4,5,6);
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insert into t6 values (13,2,3,4,5,6);
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insert into t6 values (14,2,3,4,5,6);
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insert into t6 values (15,2,3,4,5,6);
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insert into t6 values (16,2,3,4,5,6);
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insert into t6 values (17,2,3,4,5,6);
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insert into t6 values (18,2,3,4,5,6);
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insert into t7 values (1,2,3,4,5,6);
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insert into t7 values (2,2,3,4,5,6);
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insert into t7 values (3,2,3,4,5,6);
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insert into t7 values (4,2,3,4,5,6);
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insert into t7 values (5,2,3,4,5,6);
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insert into t7 values (6,2,3,4,5,6);
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insert into t7 values (7,2,3,4,5,6);
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insert into t7 values (8,2,3,4,5,6);
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insert into t7 values (9,2,3,4,5,6);
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insert into t7 values (10,2,3,4,5,6);
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insert into t7 values (11,2,3,4,5,6);
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insert into t7 values (12,2,3,4,5,6);
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insert into t7 values (13,2,3,4,5,6);
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insert into t7 values (14,2,3,4,5,6);
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insert into t7 values (15,2,3,4,5,6);
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insert into t7 values (16,2,3,4,5,6);
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insert into t7 values (17,2,3,4,5,6);
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insert into t7 values (18,2,3,4,5,6);
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insert into t7 values (19,2,3,4,5,6);
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insert into t7 values (20,2,3,4,5,6);
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insert into t7 values (21,2,3,4,5,6);
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select @@optimizer_search_depth;
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@@optimizer_search_depth
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62
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select @@optimizer_prune_level;
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@@optimizer_prune_level
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1
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set optimizer_search_depth=63;
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select @@optimizer_search_depth;
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@@optimizer_search_depth
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63
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 822.625316
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 822.625316
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 795.625316
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 795.625316
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 795.625316
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 795.625316
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set optimizer_prune_level=0;
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select @@optimizer_prune_level;
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@@optimizer_prune_level
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0
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set optimizer_search_depth=0;
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select @@optimizer_search_depth;
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@@optimizer_search_depth
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0
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 822.625316
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 822.625316
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using join buffer
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1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 290.146368
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using join buffer
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1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 290.146368
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explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
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1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
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1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
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1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
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1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
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show status like 'Last_query_cost';
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Variable_name Value
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Last_query_cost 290.146368
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explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
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1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 290.146368
|
|
set optimizer_search_depth=1;
|
|
select @@optimizer_search_depth;
|
|
@@optimizer_search_depth
|
|
1
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
set optimizer_search_depth=62;
|
|
select @@optimizer_search_depth;
|
|
@@optimizer_search_depth
|
|
62
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using join buffer
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 290.146368
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using join buffer
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 290.146368
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 290.146368
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.c21 1 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 290.146368
|
|
set optimizer_prune_level=1;
|
|
select @@optimizer_prune_level;
|
|
@@optimizer_prune_level
|
|
1
|
|
set optimizer_search_depth=0;
|
|
select @@optimizer_search_depth;
|
|
@@optimizer_search_depth
|
|
0
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
set optimizer_search_depth=1;
|
|
select @@optimizer_search_depth;
|
|
@@optimizer_search_depth
|
|
1
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
set optimizer_search_depth=62;
|
|
select @@optimizer_search_depth;
|
|
@@optimizer_search_depth
|
|
62
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t6.c62 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 822.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using index
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using index
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.c12 1 Using where
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
|
|
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t1.c14 1 Using where
|
|
1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer
|
|
1 SIMPLE t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where
|
|
show status like 'Last_query_cost';
|
|
Variable_name Value
|
|
Last_query_cost 795.625316
|
|
drop table t1,t2,t3,t4,t5,t6,t7;
|