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BUG#8924 'Explain' shows different strategy
- If number of records in table is 4, the calculated cost for using "index" and "range" become so close so that any rounding errors becomes visible. - Added one more record to the tables for heap test and expoect "range" to be selected - Decrease number of records in t1 for range and expect "index" to be choosen.
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@ -40,7 +40,7 @@ a b
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4 4
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drop table t1;
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create table t1 (a int not null) engine=heap;
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insert into t1 values (869751),(736494),(226312),(802616);
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insert into t1 values (869751),(736494),(226312),(802616),(728912);
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select * from t1 where a > 736494;
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a
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869751
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@ -66,7 +66,7 @@ a
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alter table t1 engine=myisam;
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explain select * from t1 where a in (869751,736494,226312,802616);
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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 uniq_id uniq_id 4 NULL 4 Using where; Using index
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1 SIMPLE t1 range uniq_id uniq_id 4 NULL 4 Using where; Using index
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drop table t1;
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create table t1 (x int not null, y int not null, key x (x), unique y (y))
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engine=heap;
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