如何在通用Windows应用程序中的Sqlite中更新列

Question

when i am trying to update a column in my Windows Application, i am getting error, i am using this query.
string qu = "UPDATE Registration_class SET numOfSeat = 300"; await MainPage.con.UpdateAsync(qu);

Here is the Error Screenshot

If you need any other info please tell me. Thankyou.

Answer 1

I'm not sure which sqlite version that you're using. Then if just according to the error information, you should specify the PrimaryKey for your table.

For example, like the following:

public class Registration_class
{
    [PrimaryKey, AutoIncrement]
    public int Id {get;set;}
    public string name { get; set; }
    public int numOfSeat { get; set; }
    public string password { get; set; }
}

Then I will point out another wrong place in your code. If you want to execute the sql statement directly, you should use db.Execute("UPDATE Registration_class SET numOfSeat = 300"); method, not Update method.

My code sample was based on Diederik's blog: Using SQLite on the Universal Windows Platform