DB2, C-ISAM, SQL = confusion

[Marsha]

Please bear with me on this but...

We are a small manufacturing company looking for new corporate
software (accounting, manufacturing with MRP, and sales order entry on
a Unix/Linux platform. We have narrowed our choices down to 2 vendors.
One utilizes DB2 and one utilizes C-ISAM. As I am not a database guru
(and our company does not have an MIS department) I would like to ask
the following questions:

1) Does C-ISAM = Informix?
2) Is DB2 or C-ISAM better or just different. We will have about
100,000 (including sales and inventory) records with multiple
relationships through tables.
3) We currently use Unify on a SCO Openserver and I write SQL against
it for new reports. From looking in here, I see SQL code. Does that
work with C-ISAM or is that for another product.

I have tried to find some comparisons of functionality and speed on
the web, in this group and the DB2 group with no luck. Is there
someplace you can point me for some direct comparisons? The IBM site
gave no information I could find.

Thank you for any help.

[Art S. Kagel]

On Mon, 25 Aug 2003 14:23:54 -0400, Marsha wrote:

> Please bear with me on this but...
>
> We are a small manufacturing company looking for new corporate software
> (accounting, manufacturing with MRP, and sales order entry on a
> Unix/Linux platform. We have narrowed our choices down to 2 vendors. One
> utilizes DB2 and one utilizes C-ISAM. As I am not a database guru (and
> our company does not have an MIS department) I would like to ask the
> following questions:

OK

> 1) Does C-ISAM = Informix?

No. Informix (the company) developed C-ISAM and it is the basic
underlying IO library for the Informix Standard Engine relational
database product, but the more advanced Dynamic Server products do not
even use that library.

> 2) Is DB2 or C-ISAM better or just different. We will have about 100,000
> (including sales and inventory) records with multiple relationships
> through tables.

Sounds like DB2 is what you want to use. DB2 is a relational database
management sysetem (as is IBM Informix Dynamic Server BTW) while C-ISAM
is simply a library of function calls for maintaining indexed sequential
files, which can serve as the basis for a simple or complex application
specific database system. It is possible for a C-ISAM based product to be
designed so that access to its database files is possible using the
Informix Standard Engine (SE), though I cannot say if the vendor you are
considering has done so.

> 3) We currently use Unify on a SCO Openserver and I write SQL against it
> for new reports. From looking in here, I see SQL code. Does that work
> with C-ISAM or is that for another product.

C-ISAM does not use SQL, it has only a function level interface. As I
said above, you CAN design the files and indexes carefully and name them
in such a way that you can access the files in parallel to the C-ISAM
application using SE, but that is not normally the case.

> I have tried to find some comparisons of functionality and speed on the
> web, in this group and the DB2 group with no luck. Is there someplace
> you can point me for some direct comparisons? The IBM site gave no
> information I could find.

For raw speed, if the database file design is optimized, CISAM will tend
to be faster. But the relational access will not be there. You will
sacrifice flexibility for per record access speed and for more complex
operations a fully relational database, like IDS or DB2, will often be
faster.

Art S. Kagel

> Thank you for any help.

[Mark Denham]

I would go with a product that provides an SQL interface. This will be
easier for you in the long run if you are going to do in-house stuff.

C-ISAM will almost certainly limit your options and increase the difficulty.

I am surprised that the vendor of the product that runs against DB2 does not
support other platforms, especially Oracle [burn me, in fact blow my PC up
here and now] since they have such a large market share.

Mark

----- Original Message -----
From: "Marsha" <marsha@comrex.com>
To: <informix-list@iiug.org>
Sent: Monday, August 25, 2003 14:23
Subject: DB2, C-ISAM, SQL = confusion

> Please bear with me on this but...
>
> We are a small manufacturing company looking for new corporate
> software (accounting, manufacturing with MRP, and sales order entry on
> a Unix/Linux platform. We have narrowed our choices down to 2 vendors.
> One utilizes DB2 and one utilizes C-ISAM. As I am not a database guru
> (and our company does not have an MIS department) I would like to ask
> the following questions:
>
> 1) Does C-ISAM = Informix?
> 2) Is DB2 or C-ISAM better or just different. We will have about
> 100,000 (including sales and inventory) records with multiple
> relationships through tables.
> 3) We currently use Unify on a SCO Openserver and I write SQL against
> it for new reports. From looking in here, I see SQL code. Does that
> work with C-ISAM or is that for another product.
>
> I have tried to find some comparisons of functionality and speed on
> the web, in this group and the DB2 group with no luck. Is there
> someplace you can point me for some direct comparisons? The IBM site
> gave no information I could find.
>
> Thank you for any help.

sending to informix-list