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posted @ 2021-08-25 16:22 String_y=f(x) 阅读(75) 评论(0) 推荐(0)
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posted @ 2021-06-30 09:32 String_y=f(x) 阅读(160) 评论(0) 推荐(0)
摘要: 1 SELECT ISNULL(NULL,0) WHERE ISNULL(NULL,0)=0 --实际在判断 0 = 0 2 SELECT ISNULL(' ',0) WHERE ISNULL(' ',0)=0 --实际在判断 '' = 0 ,隐式转换后是在判断0=0 3 SELECT ISNULL 阅读全文
posted @ 2021-06-23 09:40 String_y=f(x) 阅读(213) 评论(0) 推荐(0)
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posted @ 2020-09-16 13:42 String_y=f(x) 阅读(209) 评论(0) 推荐(0)