HAVING 子句對 GROUP BY 子句設置條件的方式與 WHERE 和 SELECT 的交互方式類似。WHERE 搜索條件在進行分組操作之前應用;而 HAVING 搜索條件在進行分組操作之後應用。HAVING 語法與 WHERE 語法類似,但 HAVING 可以包含聚合函數。HAVING ...
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