Re: Question on cursor location property

From: Viatcheslav V. Vassiliev (support_at_oledbdirect.com)
Date: 12/10/03 

Date: Wed, 10 Dec 2003 15:41:23 +0300

Client-side cursor works with in-memoty cache and does not retrieve data
after post. Server-side cursor has limited functionality (it does not
support sort, filter and for some providers may be forward-only read-only).

//------------------------------------------
Regards,
Vassiliev V. V.
http://www.managed-vcl.com - using .Net objects in Delphi + ADO.Net
http://www.oledbdirect.com - The fastest way to access MS SQL Server,
MS Jet (Access) and Interbase (through OLEDB)

"jacky" <_jacky@lauchuen.com_> сообщил/сообщила в новостях следующее:
news:3fd6c5c8$1@newsgroups.borland.com...
> In my case, a auto_number that will auto generate from database, which
type
> of cursor I should use if I want to get this number before post ?
>
> Actually I have tried both, when cursor location set to be Client, I can't
> get the auto_number after post until I have requery, is it the true ? On
the
> other hand, I set it to Server side cursor, this time I can get the
> auto_number after post, but some cases and exception occur "row value out
of
> range".
>
> I am using PostgreSQL and delphi 7, could you give me some hints to solve
> it.
>
> Thanks your very much.
> Jacky
>
>
> "Viatcheslav V. Vassiliev" <support@oledbdirect.com> ╪╤╪g╘С╤l╔С╥s╩D
> :3fd6bfd0$1@newsgroups.borland.com...
> > Client-side cursor fetches all rows into memory, server-side cursor
works
> > directly with DBMS, so it should be used with large datasets when
caching
> > all rows will consume too much memory. Executing updates/inserts/deletes
> > client-side cursor uses SQL query that it creates, server-side cursor
does
> > updates/insertes/deletes directly into DBMS - so with server-side cursor
> it
> > is possible to update row in table that has no primary key or unique
key,
> > client-side cursor may have problems with this. Server-side cursor does
> not
> > support filter/sort.
> >
> > //------------------------------------------
> > Regards,
> > Vassiliev V. V.
> > http://www.managed-vcl.com - using .Net objects in Delphi + ADO.Net
> > http://www.oledbdirect.com - The fastest way to access MS SQL Server,
> > MS Jet (Access) and Interbase (through OLEDB)
> >
> > "Sunny" <sunny@yahoo.com> сообщи?сообщила ?новостях следующе?
> > news:3fd693f4@newsgroups.borland.com...
> > > Hi all,
> > >
> > > In the property "Cursor Location" in ADO component, there are two
> choices
> > :
> > > clUseClient and clUseServer.
> > >
> > > I would like to know is the benefit of choosing clUseServer over
> > > clUseClient?
> > >
> > > Thanks in advance.
> > >
> > >
> >
> >
> >
>
>

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