As a result I am wanting to move the application to an SQL database.  I
currently have a Linux server with PostgreSQL, and an NT Small Business
Server with MS SQL 7. Does anyone have any experience using Delphi (I have
Professional V4, BDE 5.01) to access these database systems, and are there
any tricks or serious code modifications involved when converting from
paradox to a C/S database.

Using the PostgreSQL ODBC link, I have managed to create a very simple one
table application that is working ok.  I haven't yet managed to get anything
to communicate with the MS SQL server though - the best I can achieve is a
connection but any type of SQL query (such as CREATE TABLE) fails with
syntax errors, even though I have followed the MS documentation to the
letter.

Some of the features I need the database to be able to do include:
An equivalent of the Paradox Memo field for storing variable length text.
Referential integrity
Default values
Reliable - able to withstand a client dying with open tables (something
Paradox can't do)
and of course, it must be reasonably quick.

If at all possible, I would like to be able to have pretty much the same
code also be able to access Paradox files, as we may be deploying some
standalone versions to run on laptops, that won't have permanent access to
the main servers: As a batch process at night, the main database gets
transferred to the laptops, so that they can access the same data off-line
the next day.

Thanks in advance for any information that may be of assistance.

Have you considered InterBase.  It's not expensive and there is the
possibility to install the Local InterBase server on those laptops
(It's very lean in memory).  You would get full compatibility between
the two type of installations, without needing 'ifs' in your code.

I suggest this because what works best with Paradox (tables and
indexes) is usually the opposite of what works best on C/S servers
(queries), and the other way around.

Regards,

I see your point with local IB, and I assume that being based on C/S
architecture it would be closer to a full blown C/S solution  for code
compatibility than Paradox, even if the other database was based on a
different SQL engine.

I'm probably wrong here, but doesn't the license agreement with Local IB say
that it can only be used on the development machine for testing?

Back to my original post, does anyone have any feedback on how robust MS SQL
or PostgreSQL (or Interbase for that matter) are?  I am a little dubious.  I
have had bad experiences with other MS server products, and with PostgreSQL
being free it does give some element of doubt.  Since the information being
stored is fairly critical to the organisation, stability is a fairly
important concern.  Having said that though I am fairly confident that all
three would be streets ahead of our current networked paradox solution,
which needs the table repair utility running on it almost everytime one of
the workstations crashes.  I would greatly appreciate any comments regarding
this aspect of these servers - either on this newsgroup or direct to my emai
l: grah...@myall.net.

If I go with PostgreSQL, I will post some info with what experiences I
encountered on this NG.  From the early testing I have done it seems to
deliver exceptional performance - about a second to retrieve a 50 row result
set from a query based on two tables of around 15000 records each - and this
was done via a 33.6k modem link, from a server that is only a P133 with 32MB
RAM.   I suspect that there may also be others interested in using
PostgreSQL with Delphi.  For the small business sector, this sort of result
means that it is feasible to have high performance WAN based applications,
at a very affordable price point.  A Linux server with PostgreSQL is
certainly a heck of a lot cheaper than an NT server with MS SQL

(and remember that IB goes on Linux too).

  Server: $200
  1 user: $150
  10 user: $1200 ($120/user)
  20 user: $2100 ($105/user)

  Local IB: $100
  Local IB - 100 pack: $4000 ($40/each)

That doesn't seem like much.  I know M$ has also lowered prices on SQL
server, but I haven't seen them yet.  I think SQL server gives a bit
more headaches than IB (at least, judging from the messages in
borland.public.delphi.database.sqlservers, but it may simply be that
there are simply more people using it).

I'm sorry I can't help you on the other products.  Have you already
used PostgreSQL?  How is it?  Where can I find some info?

There is also an ODBC driver available for download, do a bit of hunting
through the links from www.postgresql.org and you should find it.
Apparently the source code can also be compiled for Windows NT - I haven't
tried this yet.

Regards,