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Server-side Cursor / Client-side Cursor

Hi
        Im trying ADOExpress with D7 and both MSSQL7 and Oracle 8i.
I understand not why Client-side cursor seems to be faster with MSSQL
and slower with Oracle, against server-side cursor are faster with
Oracle and slower with MSSQL! Can someone give me some light about this
things ?
        If I want to migrate an application from BDE to ADO that can use both
Oracle or MSSQL, need I to change the cursor type of ADOTQuery depending
on which database Im connecting to ? What is your mind about this ?

Thank you for your help.
Regards,
Michael REMY

 

Re:Server-side Cursor / Client-side Cursor


Could it have something to do with the lockmechanism?

Christophe.

Michael REMY <mich...@xmlrad.com> schreef in berichtnieuws
3DD37F0A.4040...@xmlrad.com...

Quote
> Hi
> Im trying ADOExpress with D7 and both MSSQL7 and Oracle 8i.
> I understand not why Client-side cursor seems to be faster with MSSQL
> and slower with Oracle, against server-side cursor are faster with
> Oracle and slower with MSSQL! Can someone give me some light about this
> things ?
> If I want to migrate an application from BDE to ADO that can use both
> Oracle or MSSQL, need I to change the cursor type of ADOTQuery depending
> on which database Im connecting to ? What is your mind about this ?

> Thank you for your help.
> Regards,
> Michael REMY

Re:Server-side Cursor / Client-side Cursor


Quote
>  Maybe Oracle does not
> support
> Client side cursors  at all and goes default with Server Side.

        Wow, this means that ADO with Oracle is not usable at all for a
multi-users application !? Is it this true... this is a very bad news
:-( This means I cannot use ADO for our application because it needs up
to 50 simultaneous users and we want solution that works for MSSQL AND
Oracle... Glups!

Thank you
Michael

Re:Server-side Cursor / Client-side Cursor


Client server cursors do not support record locking, because it caches all
records locally.
So it should be by default faster than Server Side .  Maybe Oracle does not
support
Client side cursors  at all and goes default with Server Side.

Michael REMY <mich...@xmlrad.com> schreef in berichtnieuws
3DD4BC0C.1070...@xmlrad.com...

Quote
> Well, it could... How can I control this or verify this point ?
> Im trying with exactly same configs for MSSQL or Oracle TADOquery
> (clClient/ctOpenForwardOnly/ltReadOnly) and on the same table structure
> (index, pk , ....) with exactly the same data (85000rows)...
> Something to do with connection parameters ?

> Michael

> Christophe a crit:
> > Could it have something to do with the lockmechanism?

> > Christophe.

> > Michael REMY <mich...@xmlrad.com> schreef in berichtnieuws
> > 3DD37F0A.4040...@xmlrad.com...

> >>Hi
> >>Im trying ADOExpress with D7 and both MSSQL7 and Oracle 8i.
> >>I understand not why Client-side cursor seems to be faster with MSSQL
> >>and slower with Oracle, against server-side cursor are faster with
> >>Oracle and slower with MSSQL! Can someone give me some light about this
> >>things ?
> >>If I want to migrate an application from BDE to ADO that can use both
> >>Oracle or MSSQL, need I to change the cursor type of ADOTQuery depending
> >>on which database Im connecting to ? What is your mind about this ?

> >>Thank you for your help.
> >>Regards,
> >>Michael REMY

Re:Server-side Cursor / Client-side Cursor


Quote
> Wow, this means that ADO with Oracle is not usable at all for a
> multi-users application !?

Not quite. It means you can't use locking. ADO will notify you if 2 users
attempt to overwrite changes when the changes are applied and you deal with
it that way.

--
Mike Collier
ADO Tool, Support & Development
Free Trial http://www.adoanywhere.com/download/aaBrowser.zip

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