> You can do the same with Paradox. You just have to take care that the
> Ttables components have they database property set to the a database
> componenet not to an alias.
> Sraya

> I have only been using TQuery and I don't plan to use TTable.
> What properties of a TDatabase do I need to set in order to use it and how
> do I connect a TQuery to it?

>I have a couple of queries about paradox databases and tables and how
>they relate to each other and how you use them. My previous experience
>with Delphi and database programming is all using MS SQL-Server. In
>these cases, the database is rather monolithic and the tables are part
>of that but with Paradox there seems to be a collection of tables with
>little apparent connection between them. (Hence the titel of the post. I
>did not mean to imply that Paradox was not a worthy database.)

>I am using Paradox tables but I do not have Paradox installed. I have
>re-installed Delphi and I now have the Database desktop which helps. I
>have made a few tables using the DD and I need to be able to read from
>and write to them in code and I have a couple of queries about how the
>BDE finds and manages tables.

> ...............
> Using the Paradox tables I have only been able to manage something like
> this:

>     Query.SQL.Add('SELECT * FROM "C:\Files\Table.db"....');

> I have a couple of queries about paradox databases and tables and how
> they relate to each other and how you use them. My previous experience
> with Delphi and database programming is all using MS SQL-Server. In
> these cases, the database is rather monolithic and the tables are part
> of that but with Paradox there seems to be a collection of tables with
> little apparent connection between them. (Hence the titel of the post. I
> did not mean to imply that Paradox was not a worthy database.)

> I am using Paradox tables but I do not have Paradox installed. I have
> re-installed Delphi and I now have the Database desktop which helps. I
> have made a few tables using the DD and I need to be able to read from
> and write to them in code and I have a couple of queries about how the
> BDE finds and manages tables.

> Using SQL-Server the way I am used to, I woul set up a TDatabase
> component that connects to the database and when I came to query the
> database, I would do something like:
>     Query.DatabaseName = Database.DatabaseName;
>     Query.SQL.Add('SELECT * FROM .....);
>     Query.Open;

> Using the Paradox tables I have only been able to manage something like
> this:

>     Query.SQL.Add('SELECT * FROM "C:\Files\Table.db"....');

> which could get a little messy if or when I move the files or distribute
> the program. I know that I could soft-code the working directory like
> so:

>     Query.SQL.Add('SELECT * FROM "' + WorkingDirectory +
> '\Table.db"....');

> but I was wondering if I am going about it all wrong and there is a
> better way to do it. Should I be using aliases? Would they make the
> installation of the program more complex or can that be done in code by,
> for example, an intallation program?

> What, if any, is the role of TDatabase when using Paradox tables and
> does the BDE keep tables open or cached or whatever to make updates nice
> and quick?
> If part of my program (a multi-threaded server) makes updates to one or
> more tables can I be reasonably sure that the other parts will get the
> freshest data possible or would I need to handle threading and
> concurrent access myself to avoid bad data and race conditions?

> As this program is (or will be) a server running as an NT service, I can
> not use data aware controls which might make the program a little easier
> to develop.
> If anyone has a demo or example program that uses Paradox tables that
> they are willing to share, I would appreciate it if they could point it
> out or send it my way.

> Thank ouy,

> In Paradox, each table is a separate file (*.db).  It may have several
> related files such as an index (*.px), memo file (*.mb) etc.  All of
> the tables and their related files in any particular directory can be
> thought of as a database.    When you create an alias, you specify its
> driver type (Paradox) and the directory that it points to.   So an
> alias can also be regarded as pointing to a database.

> If there are only one or two TQuery components in an application, you
> might create an alias (with BDE administrator) pointing to the
> directory where your Paradox tables reside.   Then you could set the
> "DatabaseName" of each TQuery to that alias, either in code or by
> selecting it using the dropdown box in the object inspector.
> Alternatively, you could omit the alias and use the directory's full
> pathname as the "DatabaseName" of the TQuery compnents.

> Then you write your sql just as in SQL Server. i.e. Select * from
> tablename.   (where tablename is the name of the paradox table. There
> is no need to include the .db extension - it is optional)

> If there are more than a couple of TQuery or Ttable components, you
> can use an TDatabase component to manage their connection to the
> database.    Set the AliasName of the TDatabase to the BDE alias that
> points to your Paradox tables.   Then set the DatabaseName of the
> TDatabase to something descriptive, say "COMPANYDB".    In this case,
> you would then set the "DatabaseName" property of all the TQuery
> components to "COMPANYDB".    Now you have the advantage of being able
> to change the database that all the components point to just by
> setting the AliasName of a single TDatabase component.

> Concerning visibility of updates, see the topic
> TDatabase.TransIsolation in the help.

> I have to question why you chose Paradox?   I am not knocking it but
> it is nearing the end of its lifespan.     Although it is reliable
> enough once you learn its quirks, it is not in the same league as a
> true client/server database.     Since your experience is with MS SQL
> Server, have you considered Interbase.  It is a true client/server
> database  with performance comparable to SQL Server but with a much
> smaller footprint, almost maintenance-free and runs on Linux, Windows
> and Solaris.   It is open source and available for free download from
> http://www.borland.com/interbase/
> You can connect to it via the BDE or ODBC or you can use the free IBX
> components to eliminate the BDE and access it directly.   ADO drivers
> are also becoming available and, unlike Paradox, it will be supported
> by Borland's new DBExpress technology in Kylix and  Delphi 6.

> regards
> Colin Acheson

> On Wed, 28 Feb 2001 15:04:50 +1100, Anthony Gilbert
> <anthony.gilb...@rmit.edu.au> wrote:

> >Hi All,

> >I have a couple of queries about paradox databases and tables and how
> >they relate to each other and how you use them. My previous experience
> >with Delphi and database programming is all using MS SQL-Server. In
> >these cases, the database is rather monolithic and the tables are part
> >of that but with Paradox there seems to be a collection of tables with
> >little apparent connection between them. (Hence the titel of the post. I
> >did not mean to imply that Paradox was not a worthy database.)

> >I am using Paradox tables but I do not have Paradox installed. I have
> >re-installed Delphi and I now have the Database desktop which helps. I
> >have made a few tables using the DD and I need to be able to read from
> >and write to them in code and I have a couple of queries about how the
> >BDE finds and manages tables.