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tell the optimizer that every TokuDB "clustering" index is the "covering" index in the MariaDB optimizer sense.
32 lines
860 B
Plaintext
32 lines
860 B
Plaintext
create table t1 (a int, b int, c text, key (a) clustering=yes, key (b)) engine=tokudb;
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) DEFAULT NULL,
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`b` int(11) DEFAULT NULL,
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`c` text,
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KEY `a` (`a`) `clustering`=yes,
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KEY `b` (`b`)
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) ENGINE=TokuDB DEFAULT CHARSET=latin1
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insert t1 values (1, 1, 1);
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insert t1 select a+1, a+1, a+1 from t1;
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insert t1 select a+2, a+2, a+2 from t1;
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insert t1 select a+4, a+4, a+4 from t1;
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select * from t1;
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a b c
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1 1 1
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2 2 2
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3 3 3
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4 4 4
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5 5 5
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6 6 6
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7 7 7
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8 8 8
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explain select a,c from t1 where a > 2;
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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 a a 5 NULL 6 Using where; Using index
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explain select b,c from t1 where b > 2;
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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 b NULL NULL NULL 8 Using where
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drop table t1;
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