1

Databases versus File Systems

It ain’t so much the things we don’t know that get us in trouble. It’s the things we know that ain’t so.

Artemus Ward (William Graham Sumner), American Writer and Humorist, 1834–1867

Databases and RDBMS in particular are nothing like the file systems that came with COBOL, FORTRAN, C, BASIC, PL/I, Java, or any of the procedural and OO programming languages. We used to say that SQL means “Scarcely Qualifies as a Language” because it has no I/O of its own. SQL depends on a host language to get and receive data to and from end users.

Programming languages are usually based on some underlying model; if you understand the model, the language makes much more sense. For example, FORTRAN is based on algebra. This does not ...

Get Joe Celko's SQL for Smarties, 4th Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.