User:Auró/sandbox 3

Basics
Basically a data base is a table containing information organized in columns and rows. Table 1 below is a simple instance of a database.

Instead of having this table, we could have the same information contained in two different tables as these.

The second arrangement is more efficient for the purposes of managing the information. These two tables contain a common column (purchase order), that is the key that makes possible to connect and ralate both tables, hence the term relational data bases.