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数据操作有关问题

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Jun 13, 2016 pm 01:22 PM

joinleftmysqlsql

数据操作问题
我目前有4张表，需要显示其中的某几个字段到页面表格中，我现在不想用left join ，我想分成4条sql来查询，然后进行组合
但是这么做会出现一个问题：搜索4张表中的某几个字段，或者对字段排序，分页，这些操作会让我的这种做饭变复杂，请问怎么才能优化这些操作

还是有其他解决方法，left join效率有些低即使加了索引，在不使用left join的情况下，怎么把这些字段放到页面表格中，并且能很方便的分页，排序，搜索！

------解决方案--------------------

探讨
我目前有4张表，需要显示其中的某几个字段到页面表格中，我现在不想用left join ，我想分成4条sql来查询，然后进行组合
但是这么做会出现一个问题：搜索4张表中的某几个字段，或者对字段排序，分页，这些操作会让我的这种做饭变复杂，请问怎么才能优化这些操作

还是有其他解决方法，left join效率有些低即使加了索引，在不使用left join的情况下，怎么把这些字段放到页面表格中，并且……

------解决方案--------------------
把字段集成到一个表中，呵呵
好好建索引不会慢到哪儿去的，只要一切规划合理的话
你必需得知道mysql有很多限制，就连索引也不是为所欲为
你对各表字段正常分类太苛刻，跨四个表，还不想联合，还嫌索引慢

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