检查记录是否存在，如果存在则“更新”，如果不存在“插入”

我想查表PREMIUM_SERVICE_USER如果存在任何记录strClientID update timeValid如果没有记录则+30strClientID插入到premium_service_user table.

我究竟做错了什么？

它增加了timeValid+30 天，但也插入另一行。

SELECT @pre_var = count(*) 
FROM PREMIUM_SERVICE_USER 
WHERE strClientID = @strClientID

/* bronze premium - 200 cash */
IF @Premium = 1
BEGIN
    INSERT INTO PREMIUM_SERVICE_USER 
        (strClientID, timeReg, timeValid, bCurrent, durum) 
    VALUES 
        (@strClientID,getdate(),getdate() + 30,'1','1')

    UPDATE TB_USER 
    SET cash = cash+200 
    WHERE strAccountID = @strClientID
END

IF @Premium = 1 AND @pre_var = 1
BEGIN
    UPDATE PREMIUM_SERVICE_USER 
        SET timevalid = timevalid+30 where strClientID = @strClientID
    UPDATE PREMIUM_SERVICE_USER 
        SET bCurrent = 1 where strClientID = @strClientID
    UPDATE TB_USER 
        SET cash = cash+200 WHERE strAccountID = @strClientID
END

你的问题是运行第一个if不考虑的价值@pre_var.

这是一种稍微不同的方法，如果PREMIUM_SERVICE_USER很大。

if @Premium = 1
  begin
    if exists(Select 1 From PREMIUM_SERVICE_USER Where strClientID = @strClientID)
      BEGIN
        update PREMIUM_SERVICE_USER set timevalid = timevalid+30 where strClientID = @strClientID
        update PREMIUM_SERVICE_USER set bCurrent = 1 where strClientID = @strClientID
        UPDATE TB_USER SET cash = cash+200 WHERE strAccountID = @strClientID
       END
    ELSE
      BEGIN
        INSERT INTO PREMIUM_SERVICE_USER (strClientID, timeReg, timeValid, bCurrent, durum) VALUES (@strClientID,getdate(),getdate() + 30,'1','1')
        UPDATE TB_USER SET cash = cash+200 WHERE strAccountID = @strClientID
       END
  end