DataAdapter.Update（）不起作用更新

Question

我的SQL statments如下 插入語句只 update和delete語句不工作

Purchase_InvoiceNo是採購表 的主鍵列我得到這個值這樣並插入其值設置爲PurchaseProduct表 「SELECT IDENT_CURRENT（ '購買'）AS [Purchase_InvoiceNo]」

 string deletecmd_PurchaseProduct = 
      @"DELETE FROM PurchaseProduct " + 
      "PurchaseProduct_No=@PurchaseProduct_No and "+ 
      "Purchase_InvoiceNo=@Purchase_InvoiceNo "; 

     string updatcmd_PurchaseProduct = 
      "UPDATE PurchaseProduct " 
     + " SET " 
     + " PurchaseProduct_SerialNo =@PurchaseProduct_SerialNo" 
     + ", Purchase_InvoiceNo =@Purchase_InvoiceNo" 
     + ", ProductNo =@ProductNo" 
     + " PurchaseProduct_Quantity =@PurchaseProduct_Quantity " 
     + ", PurchaseProduct_Unit =@PurchaseProduct_Unit" 
     + ", PurchaseProduct_Price =@PurchaseProduct_Price" 
     + " Where " 
     + " PurchaseProduct_No=@PurchaseProduct_No"; 



     string insertcmd_PurchaseProduct = "INSERT INTO PurchaseProduct" + 
          "(" + 
          " PurchaseProduct_SerialNo"+ 
          ",Purchase_InvoiceNo" + 
          ",ProductNo" + 
          ",PurchaseProduct_Quantity " + 
          ",PurchaseProduct_Price" + 
          ",PurchaseProduct_Unit" + //6 
          ")" + 
          "Values" + 
          "(" + 
          " @PurchaseProduct_SerialNo"+ 
          ",@Purchase_InvoiceNo" + 
          ",@ProductNo " + 
          ",@PurchaseProduct_Quantity " + 
          ",@PurchaseProduct_Price" + 
          ",@PurchaseProduct_Unit" +  //6 
          ");"; 

Answer 1

你刪除命令似乎是不完整的：

string deletecmd_PurchaseProduct = 
      @"DELETE FROM PurchaseProduct " + 
      "PurchaseProduct_No=@PurchaseProduct_No and "+ 
      "Purchase_InvoiceNo=@Purchase_InvoiceNo "; 

應該是：

string deletecmd_PurchaseProduct = 
      @"DELETE FROM PurchaseProduct WHERE" + 
      "PurchaseProduct_No=@PurchaseProduct_No and "+ 
      "Purchase_InvoiceNo=@Purchase_InvoiceNo "; 

我不明白爲什麼要INSERT失敗，除非你插入一個重複的主鍵值，或者你沒有把數據插入到一個非空的字段，沒有默認值。

string updatcmd_PurchaseProduct = 
     "UPDATE PurchaseProduct " 
    + "SET PurchaseProduct_SerialNo = @PurchaseProduct_SerialNo, " 
    + "Purchase_InvoiceNo = @Purchase_InvoiceNo, " 
    + "ProductNo = @ProductNo, " 
    + "PurchaseProduct_Quantity = @PurchaseProduct_Quantity, " 
    + "PurchaseProduct_Unit = @PurchaseProduct_Unit, " 
    + "PurchaseProduct_Price = @PurchaseProduct_Price " 
    + "Where PurchaseProduct_No = @PurchaseProduct_No"; 

有上面缺少逗號。