Overview of Paradox database structure and architecture

Thanks, Michelle; this was the best response I've gotten yet! I appreciate
your reply to my original posting. There were two gentlemen here; they remind
me of middle-agers, 50something, overweight, gray-haired, who think they
know it all, who claimed that I was trying to cheat my way into a position,
when all I'm trying to do is get familiar enough with paradox so that I can
speak intelligently during a possible interview. The client needs to migrate
paradox into an Access database, that's all and I know Access, but not paradox.
BTW, do you think there is documentation, out there, that shows a typical
Paradox database structure?


Michelle Burnore wrote:
>Dominick,
>
>There are numerous structures for Paradox, but these are the most common.
>
>*.Database - This is the physical table that contains your records. It looks

> virtually identical to an Access table.
>
>*.PX - If the table is keyed (same principle as in Access), there will
>be a file by the same name as the table with this extension.
>
>*.XG0, *.YG0, etc. - If there are secondary indexes on the table, there

>will be files with these or similar extensions.
>
> From within Paradox Windows, you can open the Project Viewer which
>lists Tables, Forms, Queries, Reports, etc. just as an MB file in Access

>will.
>
>Hope that helps,
>
>Michelle

Again, Paradox DOS or Windows? It makes a big difference.

Do me a favor: I realize it's a fine line between abrasive and abusive, but
can you tone down your responses?

--
Larry DiGiovanni

Dominick,

As Larry points out, Paradox DOS level tables have similar, but far more
limited field types. They are:

A - Alpha
$ - Currency
N - Number
D - Date
B - Blob
S - Short Integer
M - Memo

~Michelle


Larry DiGiovanni wrote:
> Again, Paradox DOS or Windows? It makes a big difference.

> Now, Mr. Green, do you THINK you can understand what I was saying?

yes, I understand.. you don't know anything about paradox, and think that 5
minutes with the experts will allow you to bluff your way into a job..
nothing within your rants and insults has changed that..

if I was the employer, I'd see thru that within a few seconds, and you'd be
back on the street without as much as a thank you.. I'm not trying to be
rude, I'm trying to tell you the truth.. if you think that makes me an
a*hole, so be it.. if your potential employer has a fraction of the
experience I have, I predict that you'll end up thinking he's an a*hole,
too..

--
Steven Green - Myrtle Beach, South Carolina USA

Diamond Software Group
http://www.diamondsg.com/main.htm
Paradox Support & Sales

Diamond Sports Gems
http://www.diamondsg.com/gemsmain.htm
Sports Memorabilia and Trading Cards

well spoken.

Just think - after 10 years of reading this group and making my humble
contributions, today I'm suddenly famous! And you too Steve! Of course,
your name has been mentioned previously in more glowing terms, but mine gets
very little mention. Thank god this well-meaning individual came along to
give me some press...

Well spoken Steve.

On the bright side, after 10 years of reading and contributing to this
group, I suddenly have had my name mentioned numerous times. At last - I've
got my 30 seconds!
"Steven Green" wrote in message
news:489210a7$3-at-pnews.thedbcommunity.com...
>> Now, Mr. Green, do you THINK you can understand what I was saying?
>
> yes, I understand.. you don't know anything about paradox, and think that
> 5
> minutes with the experts will allow you to bluff your way into a job..
> nothing within your rants and insults has changed that..
>
> if I was the employer, I'd see thru that within a few seconds, and you'd
> be
> back on the street without as much as a thank you.. I'm not trying to be
> rude, I'm trying to tell you the truth.. if you think that makes me an
> a*hole, so be it.. if your potential employer has a fraction of the
> experience I have, I predict that you'll end up thinking he's an a*hole,
> too..
>
> --
> Steven Green - Myrtle Beach, South Carolina USA
>
> Diamond Software Group
> http://www.diamondsg.com/main.htm
> Paradox Support & Sales
>
> Diamond Sports Gems
> http://www.diamondsg.com/gemsmain.htm
> Sports Memorabilia and Trading Cards
>
>
>

Dominick,

> There were two gentlemen here; they remind
> me of middle-agers, 50something, overweight, gray-haired, who think they
> know it all...

I belong to the same category (though not grossly overweight!) -
precisely 40 years working on Databases, Software, etc. Full-time.
Interestingly, in my experience, it's usually the young whipper-snappers
who are the "know-it-alls"... You recall that note on the side of the
fridge, from the Parents to the 20-somethings - "Move out, get yourself
an apartment, fend for yourself - while you still know everything!".

And, if YOU're not yet in that category, then, with luck, you're headed
that way!

> ...who claimed that I was trying to cheat my way into a position,
> when all I'm trying to do is get familiar enough with paradox so that I can
> speak intelligently during a possible interview.

You're splitting words here, Dominick. They all add up to the same
thing; check your thesaurus - bluff, waffle, cheat, "speak
intelligently", bullsh**, imposter, etc, etc...

And, if you get past this interview, then what? Paradox (Win or DOS), in
many respects, is more powerful than Access, and will you then be able
to unravel precisely what the Paradox app is doing, and will you be able
to implement such features in Access? What might the employer end up with?

> The client needs to migrate
> paradox into an Access database, that's all and I know Access, but not paradox.

If you review posts here over the years, you'll see many comments
suggesting that moving from Paradox to Access is the equivalent of a
"downgrade".

> BTW, do you think there is documentation, out there, that shows a typical
> Paradox database structure?

The normal documentation with Paradox is excellent, and, obviously, will
cover all your queries. And there are some 3rd party books on Paradox
also. Maybe Amazon, etc. Apart from garnering enough info for that
interview, you'll be able to concentrate on the aspects that suit your
own current Database knowledge/experiences, and you may also be able to decide
if the project is doable anyway - by you, or, indeed, by anybody!

As a general point, if you're familiar with numerous Database systems,
eg, Oracle, Sybase, MySQL, MS-SQL, PostgreSQL, DB2, etc, etc, (but not
Paradox), then you'll have no major problems getting a good handle on
Paradox, including the OPAL/PAL languages. If you know ONLY Access, and
especially if the Paradox app is a complex one, maybe you should
re-think your interview strategy at this time - the task might be very
complex. And, if I were the employer, I might not be impressed, and I
might make my views known generally...

- Mike

> -----Original Message-----
> From: Dominick [mailto:dominickdimantova-at-comcast.net]
>
> I'm asking a question, in the hopes that can get a brief overview of paradox
> structures, so that I can successfully migrate paradox tables, and other
> objects, into an Access database.
>

Jim Wrote:
>
> I see from other's responses that I wasn't the only one to misconstrue his
> question

I don't think any of us are misconstruing his question.

(Just now saw the huge list of replies - this is going to be fun. (I've
had that kind of day.))

Liz

Dominick DiMantova wrote:
> OK, thanks. Is it possible that there is a diagram of a typical paradox database
> structure, with its tables, stuff like that?
>
Access has quite a neat tool for getting an entity-relationship diagram
of a database. Paradox for Windoz does not have this. It has a fairly
crude tool for diagramming the relationships between tables, but you
have to select the ones you want and lay them out. That is, you need to
understand the ER in the first place, whereas Access can show it to you.

I have found that the nearest fit to Paradox in architecture is MySQL -
same idea of individual files to hold the tables, very similar data
types, highly compatible, easy to link with ODBC - and extremely cheap
compared to M$ offerings.

Paradox and Access do not have stored procedures and triggers.

Paradox's OPAL corresponds to Access's Visual Basic. One is pretty Basic.

Paradox's OPAL has some very neat ways of examining the database, so you
can easily develop tools for getting information about table structure,
relationships and meta-data, and documenting it as a data dictionary.

Paradox's file structure means that you must use directories to easily
make sense of the tables and other objects. For example my application
has more than 20 directories ("Forms", "Reports", "Scripts", "Queries" -
ie program objects - and "ModuleData", "CommonData", "Documentation"...
- ie data objects) which apart from making things neat and tidy allows
the M$ Windoz system to find the files quickly during operation.

Paradox scales up easily to about 400 users, unlike the Jet engine,
because usually users are not using more than a few files at the same
time, so they do not get in each others way. Bill's boys design means
that after a few users, the database engine thrashes itself trying to
handle lots of accesses (oops, I used that M$ word!) to one physical file.

BTW - we usually have quite robust and constructive conversations in
this NG without personal abuse, even when talking about M$ products.

Sorry if I have offended you, but I defend myself against the morons that
have responded to my first question. Michelle has give me the best advise
so far. I'd buy her dinner if I had the chance! I'm talking about the windows
environment, btw.


"Larry DiGiovanni" wrote:
>Again, Paradox DOS or Windows? It makes a big difference.
>
>Do me a favor: I realize it's a fine line between abrasive and abusive,
but
>can you tone down your responses?
>
>--
>Larry DiGiovanni
>
>