La logique informatique
(selon les travaux de J.D WARNIER)
L.C.S organizing data in a computer system
Discover the contents of each Primary Logical File.
That's what we have :
Sets (F.L.P)
Elements (Data fields (External mouvements))
F.L.P X
F.L.P Y
X
X
X
We must now decide whether or not an element belongs to a set.
F.L.P X
F.L.P Y
?
X
X
X
This study consists in determining whether, for an element studied, it has all the membership criteria necessary to belong to or to the sets (F.L.P) defined by comprehension.
In this study there should be no doubt, if this were the case, we would have to review the definition of the FLP's either by modifying their definitions or by modifying the subdivision of the bases, but in no case we must compromise, otherwise This is the beginning of the tote files !!!
A little anecdote ! About the files in which you find anything and everything, you computer scientists who read me, you are or have been confronted with this kind of problem:
- data fields that are blanked to indicate what are missing, data fields that are here and elsewhere, and why are they here? Etc ...
How many times have I met databases so incomprehensible that after a while nobody understands anything (except the one who manipulates them for years ...) and that there is only one Solution, is to take it all back to zero. And do not think that this concerns only the computer scientists lambda, no no I had the opportunity to work on a database of a large manufacturer (which I will not name!) And I am Still amazed at a gigantic tote, I still wonder today how it can work ?. So let's take the time, no matter how many files, the important thing is the clarity of the database (logical), after we do what we want but knowing what we do !.