Inserting data row into a sql table from another sql table in C#

Question

Context: I'm developing an app for windows in Visual Studio that has a table of stock materials and another of buyed materials, both in a Sql Server. I want that every time you buy something it is added into the stock table.

I'm new in using SQL with c# combined.

I'm trying this from a tutorial, but does nothing. Not even an exception.

            string cmdString = "Insert INTO Table1 (Column_name) VALUES (@val1)";
            string connString = @"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True";
            using (SqlConnection conn = new SqlConnection(connString))
            {
                using (SqlCommand comm = conn.CreateCommand())
                {

                    comm.Connection = conn;
                    comm.CommandText = cmdString;                    
                    comm.Parameters.AddWithValue("@val1", Value);
                    try
                    {
                        conn.Open();
                        comm.ExecuteNonQuery();
                        conn.Close()
                    }
                    catch(SqlException ex)
                    {
                        
                    }
                }
            }

Is this totally wrong or should i change something?

Edit: I figured out. I was inserting val1 in a column, but the ID was empty so it throws an NullId exception. For some reason in debug mode I wasn't able to see it.

Thanks for the help. If I have the Table1 with autoincrement why it needs an ID? There is a way that when something is inserted the Id generates automatically?

You should probably do something in the catch block. Or did you mean you never end up in the catch block? — Juho Rutila, Oct 05 '20 at 10:45
["AddWithValue is Evil"](https://www.dbdelta.com/addwithvalue-is-evil/) — sticky bit, Oct 05 '20 at 10:47
You'd be better off having a trigger execute on data insert and do the insert into the other table. — WSC, Oct 05 '20 at 10:48
It never ends in the cacth block. The database is empty because every time that you compile in visual studio the database resets. — raulmd13, Oct 05 '20 at 10:56
Every time that you compile in Visual Studio the database resets?!!! Why happen something like this? — Saeid Amini, Oct 05 '20 at 11:10
Does this answer your question? [Why saving changes to a database fails?](https://stackoverflow.com/questions/17147249/why-saving-changes-to-a-database-fails) — SMor, Oct 05 '20 at 11:33
No, I was already aware of that issue. Anyone see anything wrong in the code? — raulmd13, Oct 05 '20 at 17:18
Didn't you catch exception? Is `Column_name` a real field in your Table1? — 大陸北方網友, Oct 06 '20 at 02:47
You can't add another follow up question to your post and expect a new answer, when you do this it has the potential to invalidate previous answers and comments which later will lead to your post being closed and you may not attract a useful response. Post your additional question as a new post, it is an interesting topic that many people starting out get wrong. — Chris Schaller, Oct 07 '20 at 02:51

score 1 · Accepted Answer · edited Oct 06 '20 at 04:41

You can use this query to insert data like that :

{
    if (con.State == ConnectionState.Open)
        con.Close();
}   
{
    SqlCommand cmd0561 = new SqlCommand(@"insert into Table1 (value1,value1) values  
    (@value1,@timee)", con);
    cmd0561.Parameters.AddWithValue("@value1", value1.Text.Trim);
    cmd0561.Parameters.AddWithValue("@value2", value2.Text.Trim);
    con.Open();
    cmd0561.ExecuteNonQuery();
    con.Close();
}

Inserting data row into a sql table from another sql table in C#

1 Answers1