如果SELECT语句中没有结果,则使用CASE返回字符串

SELECT

CASE

WHEN EXISTS(

SELECT 1 FROM call_records

WHERE account = @accountnumber

)

THEN 'We Have Records of this Customer'

ELSE 'We Do Not Have Records For This Customer'

END AS 'result';

　　第二种方法：

　　IF EXISTS(SELECT SolderStatus FROM SolderInfo WHERE SolderNo='{0}') SELECT SolderStatus FROM SolderInfo WHERE SolderNo='{1}' ELSE SELECT 999 AS SolderStatus