select count(yasf) as a from random_t where yasf is null
select count(yasf) as a from random_t where len(yasf)=0
怎么查不出来
表如下:id yasf
1
2
3
4
5
6
7
8 C
9 A
select count(yasf) as a from random_t where len(yasf)=0
怎么查不出来
表如下:id yasf
1
2
3
4
5
6
7
8 C
9 A
解决方案 »
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