Chapter 4
SQL and the Relational Model
IN THIS CHAPTER
Relating SQL to the relational model
Figuring out functional dependencies
Discovering keys, views, users, privileges, schemas, and catalogs
Checking out connections, sessions, and transactions
Understanding routines and paths
The relational database model, as I mention in Chapter 1 of this minibook, existed as a theoretical model for almost a decade before the first relational database product appeared on the market. Now, it turns out that the first commercial implementation of the relational model — a software program from the company that later became Oracle — did not even use SQL, which had not yet been released by IBM. In those early days, there were a number of competing data sublanguages. Gradually, SQL became a de facto standard, thanks in no small part to IBM’s dominant position in the market, and the fact that Oracle started offering it as an alternative to its own language early on.
Although SQL was developed to work ...
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