Question

I’ve got 2 SQL commands which I need to populate a gridview. First I select every ID which the current user had filled out successfully with the following SQL command:

"SELECT Mod_ID FROM Toewijzing WHERE User_ID = '" + Session["userid"].ToString() + "' AND Toe_Status = '" + "ja" + "' "

Afterwards, for every ID found in the db I’ve got to get it’s name, language, etc etc (different table) using following SQL command:

"SELECT Mod_ID, Mod_Naam, Mod_Omschrijving, Taal_ID, User_ID from Model WHERE Mod_ID = '" + dr["Mod_ID"].ToString() + "' "

To populate my gridview I can only use 1 SQL command.
Is there any way to put these 2 commands into just 1 command?

Code used to populate the gridview:

        dr = cmd.ExecuteReader();
        gvIngevuld.DataSource = dr;
        gvIngevuld.DataBind();
        con.Close();

cmd being the SQL command.

Answer 1

Perhaps you could try this:

SELECT T.Mod_ID, M.Mod_Naam, M.Mod_Omschrijving, M.Taal_ID, M.User_ID
FROM Toewijzing T
LEFT JOIN Model M
ON T.Mod_ID = M.Mod_ID
WHERE T.User_ID = Session["userid"] AND T.Toe_Status = "ja"

If you want all users in one go, just leave off the T.User_ID condition.