File:Relational key.png

Relational Model for databases, highlighting the Key.

The image is of two tables, one storing "login," "first name," and "last name." Another table stores "login" and "phone number." The image illustrates using a unique key to link a phone number to a first and last name.

I, LionKimbro, created this image with Sodipodi. I relinquish this image into the public domain.

I am uploading to complement it.