首页 > 解决方案 > 错误:操作必须使用可更新查询

问题描述

我创建了一个程序,它将检查酒店并更新后端。我在连接和更改房间表上的用户 ID 时遇到问题。表格是:


用户:

UserID - PK, Auto Number
Username - Short Text
Password - Short Text

房间

RoomID - PK, Auto Number
Room_Number - Number
UserID - FK, Number

可更新查询

PARAMETERS parUsername Short, parRoom_Number Short;
UPDATE Rooms SET UserID = (SELECT UserID FROM Users WHERE Username = [parUsername])
WHERE Room_Number=[parRoom_Number];

C# 代码

表格1

MessageBox.Show("Login Successful");
Home home = new Home();
home.Show();
home.LabelText = this.txtUsername.Text;

主页表格

public string LabelText
        {
            get
            {
                return this.lblUsername.Text;
            }
            set
            {
                this.lblUsername.Text = value;
            }
        }

签入用户控件

 Home home = new Home();
            try
            {
                string ConnString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Application.StartupPath + "/Hotel.accdb";
                using (var con = new OleDbConnection(ConnString))
                {
                    con.Open();
                    using (var cmd = new OleDbCommand())
                    {
                        cmd.Connection = con;
                        cmd.CommandType = CommandType.StoredProcedure;
                        cmd.CommandText = "Query2";
                        cmd.Parameters.Add("parUsername", home.LabelText);
                        cmd.Parameters.Add("parRoom_Number", lbRooms.SelectedItem);
                        cmd.ExecuteNonQuery();
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

标签: c#ms-accessoledb

解决方案


而不是使用子查询,试试这个

PARAMETERS parUsername Text ( 255 ), parRoom_Number Long;
UPDATE Rooms, Users SET Rooms.UserID = Users.UserID
WHERE Rooms.Room_Number = [parRoom_Number] AND Users.Username = [parUsername];

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