In my code I have a page that includes information from 3 different tables. To show this information I make 3 SQL select calls and unite them in one list to pass as Model to my
DO NOT USE UNION.
DataAdapter is weapon of choise.
var commandText = "SELECT * FROM Table1; SELECT * FROM Table2;";
var ds = new DataSet();
using (var da = new SqlDataAdapter(commandText, "your cn"))
{
da.Fill(ds);
}