Re: Newbie question on table design.

>> In the later days of COBOL and file based applications, record definitions were stored in libraries, and referenced by COBOL source programs. These record definition libraries eventually grew into active data dictionaries. <<

The later days of COBOL??!! I hate to tell you this, but 75%+ of all commercial code on Earth is in COBOL. "Reports of my death are exaggerated." -- Mark Twain

They are not called libraries; they are called "copy books" because that is exactly what they are -- text for cut and paste.

The copy books have are no constraints, no DRI actions and if you read a file with one DATA DIVISION from a copy book, it can cheerfully cut up the bytes and fit them into that template without an error. My favorite horror story from QDB was a hospital that hung an MRI mag tape on a patient report application. The records in both files began with the patient id and that was all that was validated. It ran.

I seem to remember that data dictionaries first appeared outside of COBOL as part of the Structured Programming/ Structured Analysis movement. Yourdon, Gane & Sarson, Warnier_Orr, etc. methods defined a simple model that then grew over time when we got interactive development tools. Received on Wed May 02 2007 - 14:29:01 CDT