sas如何生成一个新的变量，表示两个相同变量出现了几次

bobguy 发表于 2013-1-11 07:37
It can be simplified as,

group 后面跟字段名和数字有哪些区别？

webgu 发表于 2013-1-11 09:47
group 后面跟字段名和数字有哪些区别？

It is no difference as long as they are referred the same variable. Here 1 means the first variable on the select list. Since wild card (*) is used, the explicit variable name referred would be a better choice.