--- In ibobjects@yahoogroups.com, <supportlist@...> wrote:

I confirm that this looks like a good way to go.

You need some exception handling added in there, but I suppose you realize that.

 

Jason

 

---

From: IBObjects@yahoogroups.com [mailto:IBObjects@yahoogroups.com] On Behalf Of soerensoerensen@...
Sent: Thursday, September 12, 2013 3:26 AM
To: IBObjects@yahoogroups.com
Subject: RE: Re: [IBO] IBO and threads

 Thank you Rob I was Down the same road but was sure if it was the proper way to do it.

--- In IBObjects@yahoogroups.com, <ibobjects@yahoogroups.com> wrote:

Hi

We do lots of threads with IBO and always use the code method.  Here is a basic example of how we do it....


procedure TMyThread.Execute;
begin
            //Create session for this thread
            ClientSesion := TIB_Session.Create(Nil);
            ClientSesion.UseCursor := False;

            //Create Database for all Query components
            IBODataBase     := TIBODatabase.Create(ClientSesion);
            IBODataBase.IB_Session      := ClientSesion;
            IBODataBase.Path                := Owner.DataBasefullPath;
            IBODataBase.SchemaCacheDir := ExtractFilePath(IBODataBase.Path);        
            IBODataBase.Server      := SystemServerName + FormattedSystemFB_Port;
            IBODataBase.Password    := WS_DB_PASSWORD;
            IBODataBase.Username    := WS_DB_USERNAME;
            IBODataBase.Protocol    := cpTCP_IP;
            IBODataBase.Connected   := True;

            fWriteTransaction            := TIB_Transaction.CreateForSession(IBODataBase, IBODataBase.IB_Session);
            fWriteTransaction.Isolation  := tiCommitted;

            fReadOnlyTransaction            := TIB_Transaction.CreateForSession(IBODataBase, IBODataBase.IB_Session);
            fReadOnlyTransaction.Isolation  := tiCommitted;
            fReadOnlyTransaction.ReadOnly   := True;              

            fGeneralQuery                   := TIBOQuery.Create(IBODataBase.IB_Session);     
            fGeneralQuery.IB_Session        := IBODataBase.IB_Session;         
            fGeneralQuery.IB_Connection     := IBODataBase;
            fGeneralQuery..IB_Transaction   := fReadOnlyTransaction ;

            fWorkControlQuery               := TIBOQuery.Create(IBODataBase.IB_Session);
            fWorkControlQuery.IB_Session    := IBODataBase.IB_Session;
            fWorkControlQuery.IB_Connection := IBODataBase;
            fWorkControlQuery.IB_Transaction:= fReadOnlyTransaction;            //RM 12/04/2006


        while (.....)
.....
        end;

        //Close and free all DB components
        i.e.
        fGeneralQuery.Active := False;
        fGeneralQuery.Free;

        fReadOnlyTransaction.Free;

        IBODataBase.Connected := False;
        IBODataBase.Free;

        ClientSesion.Free;


end;


       

The above is cleaned code from a thread in our system.  Note the Free stuff was just typed in now so could be wrong.

When creating transactions you can use CreateForSession or I believe the following is equivalent..
            fReadOnlyTransaction := TIB_Transaction.Create(IBODataBase.IB_Session);
            fReadOnlyTransaction.IB_Session := IBODataBase.IB_Session;


It is important that all DB components are created and freed as part of the TThread.execute procedure. 

Hope that helps

Cheers
Rob



 On 12/09/2013 4:55 a.m., soerensoerensen@... wrote:

 I would prefer the code solution, but how do I create a second instance of TIB_session, TIB_Cursor, TIB_connection? Could some one provide me with an example please!

--- In IBObjects@yahoogroups.com, <ibobjects@yahoogroups.com> wrote:

I recommend making a data module to hold everything that goes together.

Put a TIB_Session and however many TIB_Connection, TIB_Query, etc. components you need on that module.

Then, whe you have a need for it to be used, create a TThread and an instance of that DataModule and marry the two together.

 

You can also just do it in code without a data module. I normally start by creating a TIB_Session instance and then thereafter I use that instance as the Owner when I create the subsequent connections, queries, etc. Then, I have the thread do whatever is needed within that TIB_Session context.

 

The rule of thumb is as long as you only have a thread active within a single TIB_Session's full context you are thread safe.

 

Jason

From: IBObjects@yahoogroups.com [mailto:IBObjects@yahoogroups.com] On Behalf Of soerensoerensen@...
Sent: Tuesday, September 10, 2013 11:47 AM
To: IBObjects@yahoogroups.com
Subject: [IBO] IBO and threads

I'm developing a threaded server and use IBO and Delphi XE4. But how do I create a IBconnection, IBcursor and IBsession for each thread? I tried putting the creation under threadvar. I can compile but gets a runtime error (read access error)

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