Re: Delphi 2005, Postgresql, ZEOS & optimistic locking

You could also open a transaction and

SELECT FOR UPDATE.

So a second transaction can't Select the same data for update. That
works fine. (You can try in with pgsql too).

Daniel

Philippe Lang schrieb:

>Hi,
>
>I've been testing Delphi 2005 with Postgresql 7.4.5, through ZEOS Lib 6.5.1, and I have a question:
>
>How do you implement an optimistic locking strategy with these tools? With an Access front-end, and the ODBC driver, this is completely transparent. A test showed me that the Delphi client writes to the database without worrying about another user doing that meanwhile...
>
>I saw it's possible to manipulate the isolation level (read commited or serializable only) in the ZEOS controls, but it does not help at all here. An optimistic lock is a kind of "long transaction" for me.
>
>Thanks for your time!
>
>Philippe
>
>
>-----Message d'origine-----
>De : pgsql-general-owner(at)postgresql(dot)org [mailto:pgsql-general-owner(at)postgresql(dot)org] De la part de Arthur Hoogervorst
>Envoyé : lundi, 9. mai 2005 12:46
>À : pgsql-general(at)postgresql(dot)org
>Objet : Re: [GENERAL] Adventures in Quest for GUI RAD
>
>Hi,
>
>The company I work for actually uses the Zeos lib/Postgres extensively to track the shipping and sales side for almost 3 years.
>
>We're still running on a 7.2/7.4 Postgres database, because I haven't been convinced yet to either update or upgrade to 8.x.x. I'm curious if others have successfully moved their (production) database successfully to Postgres 8.0.
>
>
>Regards,
>
>
>Arthur
>
>On 5/9/05, Philippe Lang <philippe(dot)lang(at)attiksystem(dot)ch> wrote:
>
>
>>Hi,
>>
>>I'm testing Delphi 2005 at the moment, with ZEOS Lib (libpq), and I have to say it work fine, as Tony mentioned. I have a few questions:
>>
>>1) I'm curious: are there a lot of big projects using ZEOS with PG or is that technology still relatively new? I would like to use it a replacement for ODBC, but I have no experience regarding its stability.
>>
>>
>>
>
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