Database update/save problem

[Specter93]

I have a form that is connected to an sql database, and uses a bindingnavigator to scroll through records, add/delete/save etc. (shows data in text boxes on the form)

My problem is that when I attempt to change any of the data, I will get the following error when attempting to save: Update requires a valid UpdateCommand when passed DataRow collection with modified rows.

I've tried messing around with it a bit, like I tried just updating that specific table instead of updateall, and that looked like it worked but it never actually saved when i reopened the program. I don't really understand how to create a "valid updatecommand" so hopefully someone could explain this to me..

Thanks

[fixo]

If you use strongly typed dataset so try this

       private void saveAll()
        {
            // check changes on client side
            if (dt.GetChanges() == null)//<-- dt is datatable
                return;
            // get command builder relative to dataadapter (da) settings:
            SqlCommandBuilder cb = new SqlCommandBuilder(da);
            // bypass of parallelism error
            cb.ConflictOption = ConflictOption.OverwriteChanges;
            // updating database
            da.Update(dt);
        }
        private void saveToolStripButton_Click(object sender, EventArgs e)
        {
            if (dt.GetChanges() == null)//<-- dt is datatable
                return;
            if (!this.Validate())
            {
                MessageBox.Show("problem with validating input. Reject changes");
                return;
            }
            else
            {
                bind.EndEdit();

                saveAll();
            }
        }

Otherwise you might use a parametrizied query:

       private void saveToolStripButton_Click(object sender, EventArgs e)
        {
    
            if (!this.Validate())
            {
                MessageBox.Show("problem with validating input. Reject changes");
                return;
            }
            else
            {
                bind.EndEdit();

                SqlConnection conn = new SqlConnection(strConn);
                conn.Open();
                using (SqlCommand cmd = conn.CreateCommand())
                {
                    cmd.CommandText = insertQuey;
                    //bind is BindingSource object, that is used as DataSource of BindingNavigator:
                    cmd.Parameters.AddWithValue("@FirstName", ((DataRowView)bind.Current).Row.ItemArray[1].ToString());
                    cmd.Parameters.AddWithValue("@LastName", ((DataRowView)bind.Current).Row.ItemArray[2].ToString());
                    cmd.ExecuteNonQuery();
                    conn.Close();
                }
            }
        }

[kareninstructor]

I have a form that is connected to an sql database, and uses a bindingnavigator to scroll through records, add/delete/save etc. (shows data in text boxes on the form)

My problem is that when I attempt to change any of the data, I will get the following error when attempting to save: Update requires a valid UpdateCommand when passed DataRow collection with modified rows.

I've tried messing around with it a bit, like I tried just updating that specific table instead of updateall, and that looked like it worked but it never actually saved when i reopened the program. I don't really understand how to create a "valid updatecommand" so hopefully someone could explain this to me..

Thanks

Google is your friend here. Most likely you have not generated an update statement hence the exception

Update requires a valid UpdateCommand

http://msdn.microsoft.com/en-us/libr...wy(VS.80).aspx

Go here MDSN Social Forums which is a link to a solution and while there look at related topics on the right side of the page.

[Specter93]

Google is your friend here. Most likely you have not generated an update statement hence the exception

Update requires a valid UpdateCommand

http://msdn.microsoft.com/en-us/libr...wy(VS.80).aspx

Go here MDSN Social Forums which is a link to a solution and while there look at related topics on the right side of the page.

If I try to check the option to refresh the database like that thread recommends, when I click finish it never actually saves what I selected, and if I look at the advanced options again the refreshed option is still not checked..

[jmcilhinney]

Almost certainly, it's an issue relating to a primary key. If you are using the Data Source wizard or a CommandBuilder, in order to have DELETE and UPDATE statements generated automatically, your query must include one table only, that table must have a primary key and your query must return that primary key. Does your query satisfy those conditions?