如何样才能快速得到推荐数据
求助：怎么样才能快速得到推荐数据
是这样的我在dx_gd_goods表里有一个字段iscom标示这一条数据是推荐数据。
在数据量少的时候
select * from dx_gd_goods where iscom=1 limit 4;
但是数据量一大，上面的SQL语句取4条数据很慢，我怎么做一下，或者说设计一下才能快点呢？？
------解决方案--------------------
在 iscom 上建立索引
------解决方案--------------------
给iscom字段加索引
------解决方案--------------------
不会吧。 一个表能有两个主键？ 索引多几个没什么事。
------解决方案--------------------
加索引。
主键不会有两个。
怎么说建索引划不来呢？
像你这样的数据1 0有大量重叠的值建立索引最好不过了。
------解决方案--------------------
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