問題:mysql語句中使用like后面的%(百分號) 是不是越多執(zhí)行效率越慢!
總用時:0.0489秒 0.0691 0.0485 0.0467
SELECT `goods_name`, `goods_img`, `sku_id`, `import` FROM `goods` WHERE `goods_name` LIKE '%iPhone%iPod%' AND `stime` < 1413877244 AND `etime` > 1413877244 ORDER BY `flag` DESC
總用時: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 '%iPhone%' AND `goods_name` LIKE '%iPod%' AND `stime` < 1413877367 AND `etime` > 1413877367 ORDER BY `flag` DESC
總用時:0.0458秒 0.0441秒 0.0449秒
SELECT `goods_name`, `goods_img`, `sku_id`, `import` FROM `goods` WHERE `goods_name` LIKE '%%%%%%%%%%%%%%%%%%%%%%%iPhone%iPod%%%%%%%%%%%%%%%%%%%%%%%' AND `stime` < 1413877997 AND `etime` > 1413877997 ORDER BY `flag` DESC
實踐證明,百分號的數(shù)量不影響sql執(zhí)行的速度。這幾種方法的效率都是差不多的。
以上是我測試的結(jié)果。個人可根據(jù)自己的實際需求去選擇寫法!建議是最好選擇第二種!
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