Re: [GENERAL] Migrating from DAO 2.5 to PostgreSQL

On Sun, 1 Aug 1999 11:59:58 +0200 Elmar.Haneke@gmx.de wrote:

> Hello,
>
> I intend to migrate an VB-4 application using the DAO 2.5-Access
> database to the PostgreSQL server. Is there an simple way to do so?
>
> I did try to yust move the Tables to the Server and link them back
> into an MDB file. This works in most cases but it is not efficient
> since the DAO engine processes complex queries locally.

Whatever you do, you are going to have to modify a lot of
the queries, preferably to have the more complex of the
queries performed entirely remotely. The simplest way to do
this is to replace the current DAO queries with SQL
passthrough queries. Details of how to do this in Access
are in the Access help files. There's also ODBCDirect in
DAO, of course.

The one thing that really slows client/server down is where
data at the client end is being joined to data at the
server end.

Alternatively, you can set up the queries in PGSQL as
views, but if you want them writable, you're going to have
to write a number of rules to make sure that updates,
inserts and deletes are handled correctly. If there are a
lot of queries, then it's a lot of work.

Yours,
Moray



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Moray.McConnachie@computing-services.oxford.ac.uk