Sql server® 2012 t-sql fundamentals

The relational Model

The relational model is a semantic model for data management and manipulation and is based on 

set theory and predicate logic. As mentioned earlier, it was created by Dr. Edgar F. Codd, and later 

explained and developed by Chris Date, Hugh Darwen, and others. The first version of the relational 

model was proposed by Codd in 1969 in an IBM research report called “Derivability, Redundancy, 

and Consistency of Relations Stored in Large Data Banks.” A revised version was proposed by Codd 

in 1970 in a paper called “A Relational Model of Data for Large Shared Data Banks,” published in the 

journal Communications of the ACM.

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