Just One Pure ITer
工作中，曾有同事问我以下sql的效率如何，这里扩展一下这个问题并进行分析，主要说明where子句中的子查询和函数执行次数及索引使用情况。
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select * from trd_fundjour a where oc_date = (select collect_date from hscon.sys_arg); |
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