How can the UNION SQL clause be used?

From the name itself, you can already make a guess on what the union clause can do. It has the ability to combine two different statements. Once these statements are combined, it will form a set that will be unique of the two statements that are combined together.

This also has the ability to get rid of the duplicated in the set if in case there are any. Duplicates may cause problems with combining statements in the long run. Some get confused with the union SQL and JOIN. JOIN will form answers regarding the relationships between the statements that are given and not the statements themselves.