這是UPDATE TABLE語句正確的MSDN主題

Question

我已經看到了這類型下面的MSDN主題UPDATE語句（就像插入語句）的：

http://msdn.microsoft.com/en-us/library/aa0416cz.aspx#Y2461

UPDATE語句： -

adapter.UpdateCommand = New SqlCommand("UPDATE Customers " & 
    "(CustomerID, CompanyName) VALUES(@CustomerID, @CompanyName) " & _ 
    "WHERE CustomerID = @oldCustomerID AND CompanyName = " & 
    "@oldCompanyName", connection) 

這句話是否正確？

我試着執行它，它給出語法錯誤。

Answer 1

不，應該是：

UPDATE Customers 
SET 
CustomerID = @CustomerID, 
CompanyName = @CompanyName 
WHERE 
CustomerID = @oldCustomerID AND 
CompanyName = @oldCompanyName 

或將完整的示例代碼，它應該是：

adapter.UpdateCommand = New SqlCommand("UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName WHERE CustomerID = @oldCustomerID AND CompanyName = @oldCompanyName", connection) 

這裏是你的另一個參考，這種情況：http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldataadapter.updatecommand.aspx

Answer 2

這SQL似乎是正確的爲INSERT INTO，但沒有爲UPDATE它應該閱讀：

adapter.UpdateCommand = New SqlCommand("UPDATE Customers" & _ 
    " SET CustomerID = @CustomerID, CompanyName = @CompanyName)" & _ 
    " WHERE CustomerID = @oldCustomerID AND CompanyName =" & _ 
    " @oldCompanyName", connection) 

即SQL就是一個會叫paramaterized，這樣（在片段較低）使得這種代碼很重要：

adapter.UpdateCommand.Parameters.Add(_ 
    "@CustomerID", SqlDbType.NChar, 5, "CustomerID") 
adapter.UpdateCommand.Parameters.Add(_ 
    "@CompanyName", SqlDbType.NVarChar, 30, "CompanyName") 

' Pass the original values to the WHERE clause parameters. 
Dim parameter As SqlParameter = dataSet.UpdateCommand.Parameters.Add(_ 
    "@oldCustomerID", SqlDbType.NChar, 5, "CustomerID") 
parameter.SourceVersion = DataRowVersion.Original 
parameter = adapter.UpdateCommand.Parameters.Add(_ 
    "@oldCompanyName", SqlDbType.NVarChar, 30, "CompanyName") 
parameter.SourceVersion = DataRowVersion.Original 

Answer 3

至於我能看到語法無效。以下給出Incorrect syntax near '('.

我建議改變它按Dan's answer。

CREATE TABLE Customers 
(
CustomerID INT, 
CompanyName VARCHAR(10) 
) 

DECLARE 
@CustomerID INT, 
@CompanyName VARCHAR(10), 
@oldCustomerID INT, 
@oldCompanyName VARCHAR(10) 

UPDATE Customers (CustomerID, CompanyName) 
VALUES(@CustomerID, @CompanyName) 
WHERE CustomerID = @oldCustomerID AND CompanyName = @oldCompanyName