我可以使用SUM()MySQL中的函数轻松选择一列的总和,如下所示:
SELECT SUM(`someColumn`) FROM `table`
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是否也可以使用相同的查询返回第二列的总和?与此类似:
SELECT SUM (`someColumn`, `anotherColumn`) FROM `table`
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运行此类查询会返回以下访问冲突:
SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' `anotherColumn`) FROM `table`' at line 1
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试试:
SELECT SUM(COALESCE(`someColumn`, 0)+ COALESCE(`anotherColumn`, 0)) as TotalSum FROM `table`
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或者如果你想分开这些:
SELECT SUM(`someColumn`) as Sum1, SUM(`anotherColumn`) as Sum2 FROM `table`
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