是不是 约等于将选中的多列按照字符串拼接后去重. 不太理解 distinct 多列背后的逻辑
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zydxn 147 天前 ![]() In most cases, a DISTINCT clause can be considered as a special case of GROUP BY.
https://dev.mysql.com/doc/refman/8.0/en/distinct-optimization.html |
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breadenglish 147 天前 ![]() 是
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