All rows selected by either query including duplicate rows are retrieved.
For example, suppose you have two teams:
To create a single column of names for Team A and Team B and include duplicates, use the UNION ALL operator in the following way:
Query 1: Queries names from Team A UNION ALL Query 2: Queries names from Team B
Joe Conners Raymond Shepherd Lisa Grant Tim Collins Alison Standford Elizabeth Davis Lis Grant Raymond Shepherd Lucy Brenner Fred Lombart