Re: replication/synchronisation

On 14/9/2006 15:50, "Glenn Davy" <glenn(at)tangelosoftware(dot)net> wrote:

>> In effect, what you're trying to do is akin to what PalmOS and Lotus
>> Notes solve using synchronization systems. There aren't any tools I
>> can readily point you to to help do this with PostgreSQL, alas.
> ok thanks - Im wondering how microsoft access and mssql server seem to
> achieve this so easily - it seems to be tied up with that massively long

Only seems so easy because they have taken the time to develop the feature

> alpha unique row id (uid?) i wonder if adding similar fields (ensuring
> uniqueness could prove interesting) to all tables in any given schema
> and triggers or rules to maintain them would allow provide a basis for
> some sort of simple system? Im clearly out of my depth here - just
> puzzled why it seems so doable in some platforms and nigh impossible on
> others.

You would use a unique rowID to match rows between the two copies and two
timestamps one would be the time the server was modified the other for when
the roaming copy was modified - this will allow you to know which copy was
modified since the last synchronisation and which way to copy changes.

> I guess im wondering if there is something intrinsic to postgres that
> makes this idea prohibitive, or is it that developers already have hands
> full with other features on their minds?

No technical reason, just needs someone to take the time to do it.

> glenn
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
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>

--

Shane Ambler
Postgres(at)007Marketing(dot)com

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