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Select * 一定不走索引是否正确?

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Release: 2016-06-07 17:39:27
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Select * 一定不走索引是否正确? 走索引指的是:SQL语句的执行计划用到了1、聚集索引查找 2、索引查找 ,并且查询语句中需要有where子句 根据where子句的过滤条件,去聚集索引或非聚集索引那里查找记录 一张表只有一列的情况: 聚集索引 t1 ( id INT ) CIX_

Select * 一定不走索引是否正确?

走索引指的是:SQL语句的执行计划用到了1、聚集索引查找  2、索引查找  ,,并且查询语句中需要有where子句

根据where子句的过滤条件,去聚集索引或非聚集索引那里查找记录

一张表只有一列的情况:

聚集索引

t1 ( id INT ) CIX_T1 .(ID ASC) .( ) .

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