mysql条件应用or查询不会触发索引

WBOY
Release: 2016-06-13 11:32:24
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mysql条件使用or查询不会触发索引?
说法是:where条件中出现了or,不会使用索引


我测试结果如下:

<br />mysql> explain select * from emp where ename="dsleos" or ename="saesad" \G<br />*************************** 1. row ***************************<br />           id: 1<br />  select_type: SIMPLE<br />        table: emp<br />         type: range<br />possible_keys: e_i<br />          key: e_i<br />      key_len: 62<br />          ref: NULL<br />         rows: 2<br />        Extra: Using where<br />1 row in set (0.00 sec)<br />
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触发了索引,,到底使用or会不会触发索引啊?

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