Board index » delphi » Large Oracle databases and Delphi TQuery / TTable components

Large Oracle databases and Delphi TQuery / TTable components

If anyone has some information on the following I would appreciate it:

I am creating an application that will be using an Oracle database
running on an NT server. There is one table that will have 250000
records in the database. I am wondering what the impacts are if I use a
TQUERY vs. a TTABLE component. Specifically I noticed that a TQuery
component will fetch all records if you try to position to the bottom of
the DBGrid, while the TTable will just issue a select statement in
descending sequence. My questions are:
- If I use the TTable component, does the Oracle server populate the
cursor with all records from the 250000 record table
- Does the TQuery component populate the same as the TTable above

I am looking to make this application as fast as possible when moving
around in the table.

Thanks in advance.....

Neil Shmyr
Blueprint Solutions
NSH...@BPSOLUTIONS.COM

 

Re:Large Oracle databases and Delphi TQuery / TTable components


Quote
Neil Shmyr wrote:

> If anyone has some information on the following I would appreciate it:

> I am creating an application that will be using an Oracle database
> running on an NT server. There is one table that will have 250000
> records in the database. I am wondering what the impacts are if I use a
> TQUERY vs. a TTABLE component. Specifically I noticed that a TQuery
> component will fetch all records if you try to position to the bottom of
> the DBGrid, while the TTable will just issue a select statement in
> descending sequence. My questions are:
> - If I use the TTable component, does the Oracle server populate the
> cursor with all records from the 250000 record table
> - Does the TQuery component populate the same as the TTable above

> I am looking to make this application as fast as possible when moving
> around in the table.

I built an application for a customer that uses Oracle 7.2. It has 130k
children in it with 1300k immunizations. It has a Delphi 1 and 2 front
ends that connect  to the main server via modems.

Use TQueries.....they are much more flexable, and have less side
affects. As for going to the last record in the database...... I never
let the users do that....

hope this helps

--

Robert Schieck
-----------------------------------------------------------------------
MER Systems Inc.   voice - 416-410-5166
                  fax    - 416-410-5167

Client/Server Development and Training using Delphi,  InterBase and
Oracle

home page            http://www.mers.com
InterBase page  http://www.mers.com/interbase.html
udflib page     http://www.mers.com/product.html
TDUG page       http://www.mers.com/tdug.html      -Toronto Delphi Users Group

Other Threads