Question

我正在尝试使用另一个表的内部联接来更新用户表中的字段，但它似乎不起作用。我使用下面的代码：

        SqlCommand cmd = new SqlCommand("UPDATE U SET User.firstname = @Firstname FROM dbo.User AS U INNER JOIN dbo.Driver AS D ON U.userid = D.driverid WHERE D.driverid = @Driverid");
        cmd.CommandType = CommandType.Text;
        cmd.Connection = conn;
        cmd.Parameters.Add("@Firstname", SqlDbType.VarChar, 50).Value = firstname;
        cmd.Parameters.Add("@Driverid", SqlDbType.VarChar, 50).Value = driverid;
        conn.Open();
        cmd.ExecuteNonQuery();

SQL：

UPDATE
  U 
SET 
  User.firstname = @Firstname 
FROM 
  dbo.User AS U 
  INNER JOIN dbo.Driver AS D ON 
    U.userid = D.driverid 
WHERE
  D.driverid = @Driverid

我收到以下错误：

System.Web.Services.Protocols.SoapException：服务器无法处理请求。 ---＆GT; System.Data.SqlClient.SqlException：关键字＆＃39;用户＆＃39;

附近的语法不正确

我哪里可能出错？感谢

Answer 1

表User在您的选择部分中定义/别名为U，因此在更新字段列表中将其引用为U：

<强> EDITED ：在User周围添加了方括号，它似乎是一个保留的SQL关键字。

UPDATE
  U 
SET 
  U.firstname = @Firstname 
FROM 
  dbo.[User] AS U 
  INNER JOIN dbo.Driver AS D ON 
    U.userid = D.driverid 
WHERE
  D.driverid = @Driverid

使用内部联接执行SQL更新

1 个答案: