SQL Server MERGE into usage

DECLARE @pin varchar, @yearStr varchar set @pin = ' 01082118 ' Set @yearStr = ' MERGE into Zk_yj_manage as a USING (SE Lect @pin as ' pin ', @yearStr as ' Yearstr ') as B on (a.pin= b.pin and a.yearstr = b.yearstr) while matched     then  UPD ATE   SET basedays=17.00,dtime=getdate () when not matched then  INSERT (PIN,YEARSTR) VALUES (@pin, @yearStr);

When you write a stored procedure that handles an update insertion problem, the insert record does not exist when there is an update record.

SQL Server MERGE into usage