diff options
Diffstat (limited to 'mysql-test/main/greedy_optimizer.result')
| -rw-r--r-- | mysql-test/main/greedy_optimizer.result | 260 |
1 files changed, 130 insertions, 130 deletions
diff --git a/mysql-test/main/greedy_optimizer.result b/mysql-test/main/greedy_optimizer.result index 371dbfd8abb..90f010a898c 100644 --- a/mysql-test/main/greedy_optimizer.result +++ b/mysql-test/main/greedy_optimizer.result @@ -127,7 +127,7 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 @@ -139,55 +139,55 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 set optimizer_prune_level=0; select @@optimizer_prune_level; @@optimizer_prune_level @@ -198,108 +198,108 @@ select @@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 t2 ALL NULL NULL NULL NULL 6 Using where -1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) -1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 -1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 Using where +1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 Using where 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 2437.438350 +Last_query_cost 1.405695 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 t2 ALL NULL NULL NULL NULL 6 Using where -1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) -1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 -1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 Using where +1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 Using where 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 2437.438350 +Last_query_cost 1.405695 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 653.372751 +Last_query_cost 0.494717 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 653.372751 +Last_query_cost 0.494717 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 662.822751 +Last_query_cost 0.453737 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 662.822751 +Last_query_cost 0.453737 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 t7 index PRIMARY PRIMARY 4 NULL 21 Using index +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join) 1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) 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 (flat, BNL join) -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 2445.013350 +Last_query_cost 34.290931 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 t7 index PRIMARY PRIMARY 4 NULL 21 Using index +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join) 1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) 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 (flat, BNL join) -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 2445.013350 +Last_query_cost 34.290931 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 t3 index PRIMARY PRIMARY 4 NULL 9 Using index +1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) @@ -307,11 +307,11 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1762.798851 +Last_query_cost 14.789649 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 t3 index PRIMARY PRIMARY 4 NULL 9 Using index +1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) @@ -319,7 +319,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1762.798851 +Last_query_cost 14.789649 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 @@ -331,7 +331,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1767.523851 +Last_query_cost 1.698604 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 @@ -343,83 +343,83 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1767.523851 +Last_query_cost 1.698604 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 t2 ALL NULL NULL NULL NULL 6 Using where -1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) -1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 -1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 Using where +1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 Using where 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 2437.438350 +Last_query_cost 1.405695 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 t2 ALL NULL NULL NULL NULL 6 Using where -1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) -1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 -1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.c22 1 Using where +1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t4.c42 1 Using where 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 2437.438350 +Last_query_cost 1.405695 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 653.372751 +Last_query_cost 0.494717 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 653.372751 +Last_query_cost 0.494717 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 662.822751 +Last_query_cost 0.453737 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 (flat, BNL join) +1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) 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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where -1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 662.822751 +Last_query_cost 0.453737 set optimizer_prune_level=1; select @@optimizer_prune_level; @@optimizer_prune_level @@ -439,7 +439,7 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 @@ -451,87 +451,87 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 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 t7 index PRIMARY PRIMARY 4 NULL 21 Using index +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join) 1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) 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 (flat, BNL join) -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 2445.013350 +Last_query_cost 34.290931 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 t7 index PRIMARY PRIMARY 4 NULL 21 Using index +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join) 1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) 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 (flat, BNL join) -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 2445.013350 +Last_query_cost 34.290931 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 t3 index PRIMARY PRIMARY 4 NULL 9 Using index +1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) @@ -539,11 +539,11 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1762.798851 +Last_query_cost 14.789649 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 t3 index PRIMARY PRIMARY 4 NULL 9 Using index +1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) 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 (flat, BNL join) @@ -551,7 +551,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1762.798851 +Last_query_cost 14.789649 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 @@ -563,7 +563,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1767.523851 +Last_query_cost 1.698604 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 @@ -575,7 +575,7 @@ id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t6 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join) show status like 'Last_query_cost'; Variable_name Value -Last_query_cost 1767.523851 +Last_query_cost 1.698604 set optimizer_search_depth=62; select @@optimizer_search_depth; @@optimizer_search_depth @@ -591,7 +591,7 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 @@ -603,55 +603,55 @@ id select_type table type possible_keys key key_len ref rows Extra 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 2445.013350 +Last_query_cost 1.650792 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using index 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1330.797643 +Last_query_cost 0.578969 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 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 -1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join) +1 SIMPLE t2 ALL NULL NULL NULL NULL 6 Using where +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 t7 eq_ref PRIMARY PRIMARY 4 test.t1.c16 1 Using where 1 SIMPLE t4 ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join) +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 (flat, BNL join) +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 1334.341393 +Last_query_cost 0.577421 drop table t1,t2,t3,t4,t5,t6,t7; CREATE TABLE t1 (a int, b int, d int, i int); INSERT INTO t1 VALUES (1,1,1,1); |