[PD] pyext + pygresql vs sqlsingle

Jamie Bullock jamie at postlude.co.uk
Tue Nov 8 16:53:18 CET 2005

Thanks Carmen, and everyone else who replied so quickly to this.

I like the idea of a using a unix pipe a lot - nice and simple. Just to
confirm, did you mean something like:

mknod pgpipe p
cat pgpipe | psql -d dbname

Then in PD just collect the commands in a textfile buffer and send them
in one go at the end?

Just tried this with dummy data and it works. If I understand PD source
code correctly, textfile dynamically allocates RAM for itself as new
text is added. I can't see any upper limit on this, but I know how much
RAM I've got, and roughly how many chars I need to write, so I should be
OK, right?


On Mon, 2005-11-07 at 19:47 +0000, carmen wrote:
> On Mon, Nov 07, 2005 at 07:30:28PM +0000, Jamie Bullock wrote:
> > 
> > Dear list,
> > 
> > I need to insert around 5 sets of 40 values, per second from PD into a
> > postgresql database (both on the same machine). I can see two options -
> > pyext + pygresql or sqlsingle. 
> > 
> > >From a brief glance at both it looks like the Python route would be
> > better because sqlsingle introduces a lot of overhead
> and so does python. why not just open up a pipe (once per session) to the daemon and stream the commands over plaintext. ive not used postgres but mysql has something similar, you just terminate the message with a ";" same as pd..
> > opening and
> > closing the connection, and vacuuming the db between writes. 
> > 
> > However, perhaps sqlsingle could handle the task on a modern machine
> > (Centrino 1.6GHz)? This would probably save me some time getting the
> > Python stuff working? Does anyone have any advice either way before I
> > start with this?
> if youre generating a lot of symbols from the patch, to use as text for queries, youre going to incur ram leakage, due to the fact that PD has no 'string' type, just a never-deallocated symbol table..
> depending on how simple your database needs are, maybe you can use Pool or PDContainer instead...although theyre certainly a bit less flexible in terms of select-statement-esque things they can do the basics like retrieve via ID, next/prev, all, 'namespaces' etc..
> > 
> > -- 
> > Regards,
> > 
> > Jamie
> > 
> > 
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