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mysql千万级的count统计对比_MySQL

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Release： 2016-06-01 13:31:04
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mysql千万级的count统计对比

 

数据库：mysql 5.5 

数据量：45199077 条

 

sql语句：

[sql] select count(1) from tbresult;  select count(id) from tbresult;
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查询时间对比图：

 

mysql千万级的count统计对比_MySQL
mysql千万级的count统计对比_MySQL

 

总结：在统计查询的时候尽量使用count(id)，不要使用count(*)这样的；特别是数据量特别大的时候。

 

下面是重启后的对比图

 

mysql千万级的count统计对比_MySQL

 

重启mysql并把sql语句换位置后的结果：

 

mysql千万级的count统计对比_MySQL

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count mysql sql statement database
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