sql server 有则更新无则插入

1   string sql = " IF EXISTS(SELECT * FROM ****** WHERE ****** )  ";
2             sql += " BEGIN ";
3             sql += "  UPDATE  *****  SET  *****  WHERE **** ";
4             sql += " END ELSE BEGIN  ";
5             sql += "INSERT INTO **** (*,*,*,*)  values (*,*,*,*)      ";
6             sql += " END";
原文地址:https://www.cnblogs.com/yuyuko/p/11233037.html