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ISAM

Posted: Thu Oct 20, 2005 8:10 am
by RayBritton
Is ISAM worth learning for databases

Posted: Thu Oct 20, 2005 8:25 am
by Guest
With what I heard about it it seems convoluted

Posted: Thu Oct 20, 2005 8:54 am
by MystikShadows
ISAM had it's usefulness up to not too long ago and still do today (if you have to deal with legacy databases that you won't be porting to a new project). But if this is for your own personal use and projects, ISAM isn't really recommended....atleast I wouldn't....really depends what you want with it.

For example, if you want to make a tool that can connect to any database from other old programs (like accounting packages for example) and perform some reporting on that legacy data, then it might be helpful to learn ISAM...if you only want to create your own database for your own projects then you don't need to know ISAM.

Re: ISAM

Posted: Thu Oct 20, 2005 6:32 pm
by moneo
RayBritton wrote:Is ISAM worth learning for databases
What is called ISAM in Microsoft's PDS 7.x is a crude attempt at simulating IBM ISAM (Indexed Sequential Access Method), which was developed for IBM mainframes in the 1960's.

The IBM ISAM was only a disk access method, and not a DBMS (Data Base Management System). Hence, the ISAM in PDS 7.x is also only a disk access method, and not a database. The only database product that I know of which can be used with MSDOS QBasic programs is BTRIEVE.

I used the original IBM ISAM for several years, and was never really thrilled with it's performance. When the PDS 7.x ISAM came out, I was loaned a copy of the entire package by a local distributor to perform an evaluation. I tested the product and the ISAM for several weeks. To say the least, I found the ISAM to be terrible.

A big disadvantage of the PDS 7.x ISAM is that the files produced with this access method are totally incompatible with any other programs written in the QuickBasic/QBasic family.

So, to answer your question, ISAM is not worth learning for databases, primarily because it is not a database.
*****

Posted: Fri Oct 21, 2005 4:06 am
by RayBritton
ok thanks