Cancelling a Query running in a thread

pawelp · Post by **pawelp** » 19.01.2010, 04:53

Hi all,
how can I cancel a Zquery, which is opening in an other thread?
The Query opens some quite huge amount of data, which is displayed afterwards in a Grid.
I perform the Zquery.open call inside a separate thread, so my main Form will not be frozen.
But, the user can close this form while the thread is running. I wish to stop the thread and more importantly the Query. Is there any nice way to do it?

Many Thanks
Pawel

Post by **seawolf** » 19.01.2010, 10:34

Which database are you using? I.E. Using firebird SS (not embedded) should be quite simple

pawelp · Post by **pawelp** » 19.01.2010, 14:39

I'm using Postgres 8.3.9. ZeosLib 6.6.6-stable (from 2009-12-30). Delphi 2007.

Post by **seawolf** » 19.01.2010, 23:18

A solution, not very good, could be:

Add on the uses ZPlainPostgreSqlDriver;

On a procedure
var
PlainDriver: IZPostgreSQLPlainDriver;
begin
...
PlainDriver := IZPostgreSQLPlainDriver(ZConnection1.DbcConnection.GetIZPlainDriver);
PlainDriver.RequestCancel(ZConnection1);
...

pawelp · Post by **pawelp** » 20.01.2010, 00:38

thanks, I will try it out

pawelp · Post by **pawelp** » 20.01.2010, 01:22

One small thing so far:
GetIZPlainDriver is undeclared identifier.
But I found the proc GetDriver. I suppose that's the one.

TOLGA · Post by **TOLGA** » 08.05.2010, 00:40

I'm using firebird 2.1 ZeosLib 6.5.6-stable delphi 7
thanks for advice.

Post by **seawolf** » 08.05.2010, 17:13

I think this link and this could help you