Filterin a database at runtime

Posted on 2002-07-16
Last Modified: 2010-04-04
Hi guys!! I'm here again.

Now I have a simple question but I cannot find the solution, and I hope thay you genius will help me.

How can I specify a filter on a Paradox table at runtime?, i.e. supposing the Customer No changes according the user selection, I want to display a grid
with the invoices of that customer.
The fact is that I can't find the way to write in my source code something like Table1.Filter := ....

So, can anybody of you send me the right syntax. I think it's easy, but so far I couldn't solve it.

Thanks again

Juan Carlos
Question by:juank
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Expert Comment

ID: 7158389
Table.Filter:='some filter goes here';

Good luck!!


Expert Comment

ID: 7158396
to expand on my last comment:

Take the animals table that ships with Delphi (listed in DBDEMOS)... drop that on a form with a TTable,Datasource and a DBGrid. Now in a button click event add this code:


Now run the project... before hitting the button, you'll see every listing i the table, afterwards you'll only see those where Size>2. Alternatively, you could use a TQuery, assigning it as Dataset to the DataSource. This way you could do LIKE and ORDERBY queries as well.

Good luck!!
LVL 27

Expert Comment

ID: 7158721
you can also do a master-detail relationship between
customer-tabel and invoices-table

just set on the invoices-table as mastersource the datasource of the customer-table and set the masterfields
with the dialog there

no filter is then required,
delphi does this now automatically

meikl ;-)

Accepted Solution

marcoszorrilla earned 100 total points
ID: 7158723
More Examples with a Tedit and a Variable.

Table1.Filter:='CodCustomer ='+QuotedStr(Edit1.Text);

Table1.Filter:='CodCustomer ='+QuotedStr(MyVar);

Best Regards.

Author Comment

ID: 7165750
That's exactly what I was lookig for.


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