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BUG#14940 "MySQL choose wrong index", v.2

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- Make the range-et-al optimizer produce E(#table records after table 
                                           condition is applied),
- Make the join optimizer use this value,
- Add "filtered" column to EXPLAIN EXTENDED to show 
  fraction of records left after table condition is applied
- Adjust test results, add comments
This commit is contained in:
sergefp@mysql.com
2006-07-28 21:27:01 +04:00
parent 1459784aba
commit 699291a8e6
75 changed files with 942 additions and 683 deletions
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12
mysql-test/r/variables.result
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@@ -72,8 +72,8 @@ select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;
@t1:=(@t2:=1)+@t3:=4 @t1 @t2 @t3
5 5 1 4
explain extended select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select sql_no_cache (@t1:=((@t2:=1) + (@t3:=4))) AS `@t1:=(@t2:=1)+@t3:=4`,(@t1) AS `@t1`,(@t2) AS `@t2`,(@t3) AS `@t3`
select @t5;
@@ -132,16 +132,16 @@ select last_insert_id(345);
last_insert_id(345)
345
explain extended select last_insert_id(345);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select sql_no_cache last_insert_id(345) AS `last_insert_id(345)`
select @@IDENTITY,last_insert_id(), @@identity;
@@IDENTITY last_insert_id() @@identity
345 345 345
explain extended select @@IDENTITY,last_insert_id(), @@identity;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select sql_no_cache 345 AS `@@IDENTITY`,last_insert_id() AS `last_insert_id()`,345 AS `@@identity`
set big_tables=OFF, big_tables=ON, big_tables=0, big_tables=1, big_tables="OFF", big_tables="ON";