我有一个表格,有不同栏目中某些属性。 A栏可以是1或0。 B栏可以是`、无效或具有价值'。
我想计算一下在表A中拥有1栏的行数、在表B中列作`或无效'的行数以及B栏中未等于或等于无效的行数。
能否把所有问题都列入一个单一问题,还是我不得不提出三个不同的问题?
我使用我的智慧。 谢谢。
页: 1
SELECT COUNT(CASE WHEN A=1 THEN X END),
SUM(CASE WHEN B= OR B IS NULL THEN 1 ELSE 0 END),
SUM(CASE WHEN B= OR B IS NULL THEN 0 ELSE 1 END)
FROM YourTable
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