Question:
How do I use a SQL select statement to combine two tables that are identical in structure but contain different data?

Answer:
The union statement allows you to combine the results of two select statements, provided that the number of columns being selected and the type of the columns are equivalent.

Here is an example of a union statement the combines two lists of names in the pubs table:

u_lname, au_fnamefrom authorsunionselect lname, fnamefrom employeeorder by 1,2