Home Database Mysql Tutorial mysql语句中使用like后面的%(百分号)的问题_MySQL

mysql语句中使用like后面的%(百分号)的问题_MySQL

Jun 01, 2016 pm 01:04 PM
statement question

问题:mysql语句中使用like后面的%(百分号) 是不是越多执行效率越慢!

总用时:0.0489秒 0.0691 0.0485 0.0467

SELECT `goods_name`, `goods_img`, `sku_id`, `import` FROM `goods` WHERE `goods_name` LIKE &#39;%iPhone%iPod%&#39; AND `stime` < 1413877244 AND `etime` > 1413877244 ORDER BY `flag` DESC
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总用时:0.0460秒 0.0430 0.0493 0.0783 0.0496
SELECT `goods_name`, `goods_img`, `sku_id`, `import` FROM `goods` WHERE `goods_name` LIKE &#39;%iPhone%&#39; AND `goods_name` LIKE &#39;%iPod%&#39; AND `stime` < 1413877367 AND `etime` > 1413877367 ORDER BY `flag` DESC
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总用时:0.0458秒 0.0441秒 0.0449秒

SELECT `goods_name`, `goods_img`, `sku_id`, `import` FROM `goods` WHERE `goods_name` LIKE &#39;%%%%%%%%%%%%%%%%%%%%%%%iPhone%iPod%%%%%%%%%%%%%%%%%%%%%%%&#39; AND `stime` < 1413877997 AND `etime` > 1413877997 ORDER BY `flag` DESC
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实践证明,百分号的数量不影响sql执行的速度。这几种方法的效率都是差不多的。

以上是我测试的结果。个人可根据自己的实际需求去选择写法!建议是最好选择第二种!

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