摘要:        
select * , t3.Name from t1 left join t2 on t1.sysno = t2.Asysno left join t3 on t3.sysno = t2.Bsysno 上面SQL语句中,t3表数据很多;此时查询t3.Name会很慢,如果把t3和name干掉,秒中就能    阅读全文
posted @ 2016-11-30 12:01
名字什么都是浮云
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摘要:        
select * from t1 left join t2 on t2.sysno =t1.ASysNo left join t3 on t3.sysno =t2.ASysNo left join t4 on t4.sysno =t3.ASysNo left join t5 on t5.sysno     阅读全文
posted @ 2016-11-30 10:45
名字什么都是浮云
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浙公网安备 33010602011771号