13 lines
557 B
Plaintext
13 lines
557 B
Plaintext
drop table if exists t1;
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create table t1(n int not null, key(n)) delay_key_write = 1;
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select count(distinct n) from t1;
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count(distinct n)
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100
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explain extended select count(distinct n) from t1;
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t1 NULL range n n 4 NULL 21 100.00 Using index for group-by
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Warnings:
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Warning 1681 'EXTENDED' is deprecated and will be removed in a future release.
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Note 1003 /* select#1 */ select count(distinct `test`.`t1`.`n`) AS `count(distinct n)` from `test`.`t1`
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drop table t1;
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