Third normal form wants us to remove transitive dependencies. A transitive dependency exists when a column depends on the primary key through another column. We need to make this column depend only on the primary key, so to do this we need to move some stuff to a new table. The example we gave in this video was with listings. Each listing can have a category, and each category has a description. In order for us to make the category_description focus only on the primary key, we have to move the category column into a new table called categories. Then in the original table we reference this data with a foreign key. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me! www.patreon.com/calebcurry Subscribe to my newsletter: eepurl.com/-8qtH Donate!: bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: CalebCurry.com Facebook: www.facebook.com/CalebTheVideoMaker Google+: plus.google.com/+CalebTheVideoMaker2 Twitter: twitter.com/calebCurry Amazing Web Hosting - www.dreamhost.com/r.cgi?1487063 (The best web hosting for a cheap price!)

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