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Thread tips and hints to convert from Paradox
Mon, Feb 20 2006 7:54 AMPermanent Link

"Santy Concepción"
Hi!

After a few months trying DBISAM, we are going to convert our old Parado/BDE
applicatoin to DBISAM.

Are there any inconveniences, tips, hints, things to be careful with,
etc...?

Thanks!!

Mon, Feb 20 2006 9:01 AMPermanent Link

Dan Rootham
Santy,

<< After a few months trying DBISAM, we are going to convert our old Parado/BDE
applicatoin to DBISAM. Are there any inconveniences, tips, hints, things to be careful with,
etc...? >>

It's along time since I converted from Paradox to DBISAM, but I do remember that
we had problems with accented characters getting trashed in Portuguese, German etc.
Might be worth running some tests to make sure that the import does preserve the
non-ASCII characters. Some of the Paradox language drivers were... interesting.

HTH,
Dan
Mon, Feb 20 2006 9:07 AMPermanent Link

Roy Lambert

NLH Associates

Team Elevate Team Elevate

Santy


Do the conversion in the first instance just by going a global search and replace on the component names.

Avoid OnFilter event if possible.

If using threads make sure you observe the rules in the manual, if not prepare for disaster!

Check all SQL - DBISAM is better but more stringent than Paradox/BDE (double quote vs single quote for example)

Generally though it should be fairly simple.


Roy Lambert
Mon, Feb 20 2006 12:38 PMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

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Email timyoung@elevatesoft.com

Dan,

<< It's along time since I converted from Paradox to DBISAM, but I do
remember that we had problems with accented characters getting trashed in
Portuguese, German etc. Might be worth running some tests to make sure that
the import does preserve the non-ASCII characters. Some of the Paradox
language drivers were... interesting. >>

That's probably the transliterate issue - you had to make sure to check the
Transliterate check box in the BDE Database Transfer Utility in order to
keep the high ASCII characters during the conversion.  Also, I believe that
initially (way back when Smiley, BDETran didn't have a transliterate option.

--
Tim Young
Elevate Software
www.elevatesoft.com

Mon, Feb 20 2006 4:16 PMPermanent Link

"Adam H."
Another one for the list...

Make sure you optimise your queries by adding indexes for the fields that
you will use. In Paradox with the BDE, we were allowed to remain sloppy,
because I believe the BDE created some indexes on the fly (?) in order to
execute the query fast.

With DBISam, if you don't optimise your queries, you will see a very
noticeable difference in time on larger tables. It's easy to fix, but just
one to be aware of.

Apart from that - You'll love DBISam. Seriously. (I've come from the same
background as you!)  I'm doing things in Queries I could have never done
before with the BDE. Some of my faviourites are Memory queries, allowing me
to do "queries on queries", and the ability to perform multiple SQL queries
in the one component (by seperating each query with the semicolumn delimiter
';') Oh, and the fact that their are no additional engines, DLL's,
installations, etc to worry about - that DBISam compiles direct into your
exe - no more configuration required - that rocks!

Tim - out of curiosity, did I read somewhere that ElevateDB will create
Indexes on the fly, to automatically optimise queries?

Cheers

Adam.

Tue, Feb 21 2006 12:49 PMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

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Email timyoung@elevatesoft.com

Adam,

<< Tim - out of curiosity, did I read somewhere that ElevateDB will create
Indexes on the fly, to automatically optimise queries? >>

Actually, no.  However, if you use the constraints properly, then most
tables will already have primary, unique, and foreign keys on all of the
important columns already, hence joins and searching will be fast.

--
Tim Young
Elevate Software
www.elevatesoft.com

Tue, Feb 21 2006 1:22 PMPermanent Link

"Jose Eduardo Helminsky"
Tim

I understand you point but I think that sometimes we need to query using a
"non-important" field and in that way the speed will be slow. It will be a
good feature for ElevateDB.

Eduardo

Tue, Feb 21 2006 3:49 PMPermanent Link

"Santy Concepción"
Ho, Roy...

Why to avoid using OnFilter event?
We have a search option that uses this event in our app.


"Roy Lambert" <roy.lambert@skynet.co.uk> escribió en el mensaje
news:3A96CE2E-5F45-412D-89C9-DE10D27F1564@news.elevatesoft.com...
> Santy
>
>
> Do the conversion in the first instance just by going a global search and
> replace on the component names.
>
> Avoid OnFilter event if possible.
>
> If using threads make sure you observe the rules in the manual, if not
> prepare for disaster!
>
> Check all SQL - DBISAM is better but more stringent than Paradox/BDE
> (double quote vs single quote for example)
>
> Generally though it should be fairly simple.
>
>
> Roy Lambert
>

Tue, Feb 21 2006 7:01 PMPermanent Link

"Adam H."
Hi Santy,

I think the idea is, if you can do a filter / query any other way, do it
another way, but if not, use the onfilter event.

The onfilter event, IIRC - needs to load every record in the table / result
before it does the query, and does not use the speed benefits you obtain
with indexes. This will slow down your application (as it always has).

If you're happy with the speed you currently get out of the onfilterevent,
you probably won't have a problem, unless your data grows significantly.

Regards

Adam.

Wed, Feb 22 2006 6:27 PMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

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Email timyoung@elevatesoft.com

Eduardo,

<< I understand you point but I think that sometimes we need to query using
a "non-important" field and in that way the speed will be slow. It will be a
good feature for ElevateDB. >>

I understand, however there are issues with creating indexes "on the fly" in
a multi-user scenario that are very difficult to overcome given the current
architecture.

--
Tim Young
Elevate Software
www.elevatesoft.com

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