Questions tagged [codds-rules]

Codd's rules are a series of practical guidelines for a database system to be considered relational. They are derived from Codd's relational calculus. They are implemented to a greater or lesser degree by all the major RDBMS providers, albeit perfectly by none of them!

Please see here and here for more information.

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Why does metadata have to stored in table cells according to Codd's 12 rules

Among Codd's 12 rules for Relational Database Management Systems is Rule 1, which states the following: Rule 1: Information rule All information(including metadata) is to be represented as stored data in cells of tables. The rows and columns have…
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RDBMS: Proper way to store data - comma separated variables or in different fields or tables?

Fundamental question that I cannot seem to find an answer on. I have a database that stores line items from receipts along with the username and receipt number. Right now the lineItem column is just a long string of data separated by commas…
Bunny
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What does relational capabilities mean in Codd's Foundation rule?

From Codd's 12 rules (emphasis mine): For any system that is advertised as, or claimed to be, a relational data base management system, that system must be able to manage data bases entirely through its relational capabilities. What does…