mirror of
https://github.com/MariaDB/server.git
synced 2025-07-27 18:02:13 +03:00
Change cost for REF to take into account cost for 1 extra key read_next
The main difference in code path between EQ_REF and REF is that for REF we have to do an extra read_next on the index to check that there is no more matching rows. Before this patch we added a preference of EQ_REF by ensuring that REF would always estimate to find at least 2 rows. This patch adds the cost of the extra key read_next to REF access and removes the code that limited REF to at least 2 rows. For some queries this can have a big effect as the total estimated rows will be halved for each REF table with 1 rows. multi_range cost calculations are also changed to take into account the difference between EQ_REF and REF. The effect of the patch to the test suite: - About 80 test case changed - Almost all changes where for EXPLAIN where estimated rows for REF where changed from 2 to 1. - A few test cases using explain extended had a change of 'filtered'. This is because of the estimated rows are now closer to the calculated selectivity. - A very few test had a change of table order. This is because the change of estimated rows from 2 to 1 or the small cost change for REF (main.subselect_sj_jcl6, main.group_by, main.dervied_cond_pushdown, main.distinct, main.join_nested, main.order_by, main.join_cache) - No key statistics and the estimated rows are now smaller which cased estimated filtering to be lower. (main.subselect_sj_mat) - The number of total rows are halved. (main.derived_cond_pushdown) - Plans with 1 row changed to use RANGE instead of REF. (main.group_min_max) - ALL changed to REF (main.key_diff) - Key changed from ref + index_only to PRIMARY key for InnoDB, as OPTIMIZER_ROW_LOOKUP_COST + OPTIMIZER_ROW_NEXT_FIND_COST is smaller than OPTIMIZER_KEY_LOOKUP_COST + OPTIMIZER_KEY_NEXT_FIND_COST. (main.join_outer_innodb) - Cost changes printouts (main.opt_trace*) - Result order change (innodb_gis.rtree)
This commit is contained in:
Monty
@ -3125,15 +3125,15 @@ t1.metaid = t2.metaid AND t1.affiliateid = '2';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t6 system PRIMARY NULL NULL NULL 1
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1 SIMPLE t5 ref PRIMARY,t5_formattypeid t5_formattypeid 4 const 1
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1 SIMPLE t9 index PRIMARY,t9_subgenreid,t9_metaid PRIMARY 8 NULL 2 Using index; Using join buffer (flat, BNL join)
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t9.metaid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t4 ref PRIMARY,t4_formatclassid,t4_formats_idx t4_formatclassid 4 test.t5.formatclassid 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t3 ref t3_metaid,t3_formatid,t3_metaidformatid t3_formatid 4 test.t4.formatid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t1 ref t1_affiliateid,t1_metaid t1_metaid 4 test.t3.metaid 1 Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t3.metaid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t7 ref PRIMARY PRIMARY 4 test.t3.metaid 1 Using index
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1 SIMPLE t8 eq_ref PRIMARY PRIMARY 4 test.t7.artistid 1 Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t9 ref PRIMARY,t9_subgenreid,t9_metaid t9_metaid 4 test.t3.metaid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t10 eq_ref PRIMARY,t10_genreid PRIMARY 4 test.t9.subgenreid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t11 eq_ref PRIMARY PRIMARY 4 test.t10.genreid 1 Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t7 ref PRIMARY PRIMARY 4 test.t9.metaid 1 Using index
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1 SIMPLE t8 eq_ref PRIMARY PRIMARY 4 test.t7.artistid 1 Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t3 ref t3_metaid,t3_formatid,t3_metaidformatid t3_metaidformatid 4 test.t9.metaid 1 Using index condition; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t4 eq_ref PRIMARY,t4_formatclassid,t4_formats_idx PRIMARY 4 test.t3.formatid 1 Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t1 ref t1_affiliateid,t1_metaid t1_affiliateid 4 const 2 Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
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SELECT t1.uniquekey, t1.xml AS affiliateXml,
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t8.name AS artistName, t8.artistid,
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t11.name AS genreName, t11.genreid, t11.priority AS genrePriority,
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@ -3273,7 +3273,7 @@ EXPLAIN
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SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
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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 5
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1 SIMPLE t2 ref i_a i_a 4 test.t1.a 2 Using where; Not exists
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1 SIMPLE t2 ref i_a i_a 4 test.t1.a 1 Using where; Not exists
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SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
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a a b
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3 NULL NULL
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@ -3284,7 +3284,7 @@ EXPLAIN
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SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
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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 5
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1 SIMPLE t2 ref i_a i_a 4 test.t1.a 2 Using where; Not exists; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref i_a i_a 4 test.t1.a 1 Using where; Not exists; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
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a a b
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3 NULL NULL
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@ -3311,7 +3311,7 @@ select t1.a, count(t2.p) as count
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from t1 left join t2 on t1.a=t2.a and t2.p % 2 = 1 group by t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 4 NULL 8 Using index; Using temporary; Using filesort
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1 SIMPLE t2 ref i_a i_a 5 test.t1.a 2 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref i_a i_a 5 test.t1.a 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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select t1.a, count(t2.p) as count
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from t1 left join t2 on t1.a=t2.a and t2.p % 2 = 1 group by t1.a;
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a count
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@ -4085,7 +4085,7 @@ 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 2
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join)
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1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.carrier 1 Using where
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1 SIMPLE t4 ref carrier_id carrier_id 5 test.t3.id 2 Using index
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1 SIMPLE t4 ref carrier_id carrier_id 5 test.t3.id 1 Using index
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SET join_cache_level=@save_join_cache_level;
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DROP TABLE t1,t2,t3,t4;
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#
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@ -4101,7 +4101,7 @@ set join_cache_level = 5;
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explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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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 2
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1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref b b 5 test.t1.b 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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a
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NULL
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@ -4110,7 +4110,7 @@ set join_cache_level = 8;
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explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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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 2
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1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref b b 5 test.t1.b 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
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SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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a
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NULL
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@ -4121,7 +4121,7 @@ set join_cache_level = 5;
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explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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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 2
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1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref b b 5 test.t1.b 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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a
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NULL
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@ -4136,7 +4136,7 @@ set join_cache_level = 5;
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explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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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 2
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1 SIMPLE t2 ref b b 103 test.t1.b 2 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref b b 103 test.t1.b 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
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SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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a
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NULL
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@ -4145,7 +4145,7 @@ set join_cache_level = 8;
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explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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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 2
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1 SIMPLE t2 ref b b 103 test.t1.b 2 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
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1 SIMPLE t2 ref b b 103 test.t1.b 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
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SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
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a
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NULL
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@ -4529,7 +4529,7 @@ EXPLAIN
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SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
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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
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1 SIMPLE t1 ref cu cu 33 func 2 Using where; Using index
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1 SIMPLE t1 ref cu cu 33 func 1 Using where; Using index
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SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
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i
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6
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@ -4862,7 +4862,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
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1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 1 100.00 Using where
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1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where
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Warnings:
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Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(`test`.`t2`.`d2` = `test`.`t1`.`pk` and `test`.`t3`.`a3` = `test`.`t2`.`c2`) left join `test`.`t4` on(`test`.`t4`.`a4` = `test`.`t1`.`a1` and `test`.`t1`.`a1` is not null) left join `test`.`t5` on(`test`.`t5`.`a5` = `test`.`t3`.`a3`) where 1
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@ -4884,7 +4884,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
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1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (incremental, BNL join)
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 1 100.00 Using where
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1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
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Warnings:
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Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(`test`.`t2`.`d2` = `test`.`t1`.`pk` and `test`.`t3`.`a3` = `test`.`t2`.`c2`) left join `test`.`t4` on(`test`.`t4`.`a4` = `test`.`t1`.`a1` and `test`.`t1`.`a1` is not null) left join `test`.`t5` on(`test`.`t5`.`a5` = `test`.`t3`.`a3`) where 1
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@ -4906,7 +4906,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
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1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
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1 SIMPLE t4 ref idx idx 5 test.t1.a1 1 100.00 Using where
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1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
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Warnings:
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Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(`test`.`t2`.`d2` = `test`.`t1`.`pk` and `test`.`t3`.`a3` = `test`.`t2`.`c2`) left join `test`.`t4` on(`test`.`t4`.`a4` = `test`.`t1`.`a1` and `test`.`t1`.`a1` is not null) left join `test`.`t5` on(`test`.`t5`.`a5` = `test`.`t3`.`a3`) where 1
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@ -5154,7 +5154,7 @@ EXPLAIN SELECT * FROM t1,t2
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WHERE t2.f3 = t1.f2 AND t1.f1 IN (9, 0, 100) ORDER BY t1.f2 LIMIT 1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range f1,f2 f1 5 NULL 3 Using where; Rowid-ordered scan; Using filesort
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1 SIMPLE t2 ref f3 f3 67 test.t1.f2 2 Using where; Using index
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1 SIMPLE t2 ref f3 f3 67 test.t1.f2 1 Using where; Using index
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SELECT * FROM t1,t2
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WHERE t2.f3 = t1.f2 AND t1.f1 IN (9, 0 ,100) ORDER BY t1.f2 LIMIT 1;
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f1 f2 f3
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@ -5164,7 +5164,7 @@ EXPLAIN SELECT * FROM t1,t2
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WHERE t2.f3 = t1.f2 AND t1.f1 IN (9, 0 ,100) ORDER BY t1.f2 LIMIT 1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range f1,f2 f1 5 NULL 3 Using index condition; Using where; Rowid-ordered scan; Using filesort
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1 SIMPLE t2 ref f3 f3 67 test.t1.f2 2 Using where; Using index
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1 SIMPLE t2 ref f3 f3 67 test.t1.f2 1 Using where; Using index
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SELECT * FROM t1,t2
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WHERE t2.f3 = t1.f2 AND t1.f1 IN (9, 0 ,100) ORDER BY t1.f2 LIMIT 1;
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f1 f2 f3
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@ -5265,7 +5265,7 @@ EXPLAIN
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SELECT a FROM t1,t2 WHERE t2.v = t1.v ;
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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 2 Using where
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1 SIMPLE t2 ref idx idx 4 test.t1.v 2
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1 SIMPLE t2 ref idx idx 4 test.t1.v 1
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SELECT a FROM t1,t2 WHERE t2.v = t1.v ;
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a
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11
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@ -5323,7 +5323,7 @@ EXPLAIN
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SELECT * FROM t1 WHERE (t1.b) IN (SELECT c FROM t2);
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
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1 PRIMARY t2 ref c c 5 test.t1.b 2 Using index; Start temporary; End temporary
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1 PRIMARY t2 ref c c 5 test.t1.b 1 Using index; Start temporary; End temporary
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SELECT * FROM t1 WHERE (t1.b) IN (SELECT c FROM t2);
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a b
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3914 17
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@ -5503,7 +5503,7 @@ id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system NULL NULL NULL NULL 1
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1 PRIMARY t3 system NULL NULL NULL NULL 1
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1 PRIMARY t2 range a,c a 5 NULL 2 Using index condition; Using where; Using filesort
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1 PRIMARY t4 ref c c 5 test.t2.c 2 Using where; Start temporary; End temporary
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1 PRIMARY t4 ref c c 5 test.t2.c 1 Using where; Start temporary; End temporary
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SELECT * FROM t1,t2
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WHERE t2.c IN (SELECT c FROM t3,t4 WHERE t4.a < 10) AND
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t2.a BETWEEN 4 and 5
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@ -5521,7 +5521,7 @@ id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system NULL NULL NULL NULL 1 Using temporary; Using filesort
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1 PRIMARY t3 system NULL NULL NULL NULL 1
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1 PRIMARY t2 range a,c a 5 NULL 2 Using index condition; Using where
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1 PRIMARY t4 ref c c 5 test.t2.c 2 Using where; Start temporary; End temporary
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1 PRIMARY t4 ref c c 5 test.t2.c 1 Using where; Start temporary; End temporary
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SELECT * FROM t1,t2
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WHERE t2.c IN (SELECT c FROM t3,t4 WHERE t4.a < 10) AND
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t2.a BETWEEN 4 and 5
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@ -5540,7 +5540,7 @@ id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system NULL NULL NULL NULL 1 Using temporary; Using filesort
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1 PRIMARY t3 system NULL NULL NULL NULL 1
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1 PRIMARY t2 range a,c a 5 NULL 2 Using index condition; Using where
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1 PRIMARY t4 ref c c 5 test.t2.c 2 Using where; Start temporary; End temporary
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1 PRIMARY t4 ref c c 5 test.t2.c 1 Using where; Start temporary; End temporary
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SELECT * FROM t1,t2
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WHERE t2.c IN (SELECT c FROM t3,t4 WHERE t4.a < 10) AND
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t2.a BETWEEN 4 and 5
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@ -5583,7 +5583,7 @@ and t2.uid=t1.fid;
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t3 ref uid uid 5 const 4 Using where; Start temporary
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1 PRIMARY t4 eq_ref PRIMARY PRIMARY 4 test.t3.fid 1 Using index
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1 PRIMARY t1 ref uid uid 5 test.t3.fid 2 Using where; End temporary; Using join buffer (flat, BKAH join); Rowid-ordered scan
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1 PRIMARY t1 ref uid uid 5 test.t3.fid 1 Using where; End temporary; Using join buffer (flat, BKAH join); Rowid-ordered scan
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1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t1.fid 1 Using join buffer (flat, BKAH join); Rowid-ordered scan
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select name from t2, t1
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where t1.uid in (select t4.uid from t4, t3 where t3.uid=1 and t4.uid=t3.fid)
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