如果存在更新，否則插入

Question

我想知道下一段代碼是否正確：

 SqlCommand cmd = new SqlCommand(
   "IF NOT EXISTS(SELECT count(*) from Raspunsuri where id_intrebare=2)" +
   "Insert INTO Raspunsuri VALUES(@raspuns,@cnp,@data,2,@ip,@idsesiune)" +
   "else" +
   "UPDATE Raspunsuri SET raspuns=@raspuns,cod_numeric_personal=@cnp,data_raspuns=@data,id_intrebare=2,ip_user=@ip,id_sesiune=@idsesiune WHERE id_intrebare=2", con);

我想插入的所有參數都是正確的，但是似乎這段代碼沒有執行插入或更新操作。您有什么建議嗎？這是與c＃結合使用的sql查詢。

Answer 1

檢查該命令創建的字符串：某些單詞之間需要空格。

 SqlCommand cmd = new SqlCommand("IF NOT EXISTS(SELECT 1 from Raspunsuri where id_intrebare=2)" +
                " Insert INTO Raspunsuri VALUES(@raspuns,@cnp,@data,2,@ip,@idsesiune)" +
                " else" +
                " UPDATE Raspunsuri SET raspuns=@raspuns,cod_numeric_personal=@cnp,data_raspuns=@data,id_intrebare=2,ip_user=@ip,id_sesiune=@idsesiune WHERE id_intrebare=2", con);

Answer 2

描述

否，因為您選擇的count始終是一個值。

選擇一列或* 。

樣品

SqlCommand cmd = new SqlCommand(
   "IF NOT EXISTS(SELECT id_intrebare from Raspunsuri where id_intrebare=2) " +
   "Insert INTO Raspunsuri VALUES(@raspuns,@cnp,@data,2,@ip,@idsesiune) " +
   "else " +
   "UPDATE Raspunsuri SET raspuns=@raspuns,cod_numeric_personal=@cnp,data_raspuns=@data,id_intrebare=2,ip_user=@ip,id_sesiune=@idsesiune WHERE id_intrebare=2", con);

Answer 3

您為什么不使用MERGE命令？

Answer 4

您可以先嘗試在SQL Server Management Studio窗口中執行查詢。 這將為您提供調試事物的簡便方法

Answer 5

我認為“ else”語句之間缺少空格還請確保您已在values部分提供了所有列