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</html><description>Dr. Codd proposed the normalization rules we used to design databases, but did you know that he also came up with rules that vendors must meet to call their products relational database systems? In this article, Joe Celko explains the thirteen RDBMS rules.</description><thumbnail_url>https://www.red-gate.com/simple-talk/wp-content/uploads/2024/07/simple-talk-dark-background.jpg</thumbnail_url><thumbnail_width>1500</thumbnail_width><thumbnail_height>1000</thumbnail_height></oembed>
