[support] Drupal: MySQL vs. PostgreSQL

[Pierre Rineau]

Le mercredi 21 juillet 2010 à 11:49 +0530, Nilesh Govindarajan a écrit :
> On Wed, Jul 21, 2010 at 4:50 AM, Kevin Davison <kevin at quevin.com> wrote:
> > I'm not very familiar with the use of PostgreSQL with Drupal, as I tend to
> > use Pressflow with MySQL on most projects. I read about the advantages and
> > disadvantages, but not sure how to compare a clustered DB with PostgreSQL
> > and Pressfow running on Pantheon with MySQL optimized, perhaps on multiple
> > DB servers. It looks like there are various issues with contributed modules
> > & PostgreSQL, and that doesn't sound like much fun to deal with.
> > So now I have a potential client who needs help with PostgreSQL in the mix,
> > and I'm not sure if I should get involved.
> > Here's the client's development/production environment:
> >
> 
> As per my personal experience, I feel Postgresql is much much faster
> then Mysql (both properly configured and optimized, include compiler
> optimizations).
> My site loads at lightning speed on Postgresql, with Mysql it used to
> near take about a minute.
> Please other Mysql fans, don't start flame wars here, its just my
> personal experience.
> 
> Further, don't use Postgresql unless you have good knowledge of SQL
> and PHP, because many modules have SQL syntax which works only on
> Mysql, so you need to tweak those scripts to get them working with
> Postgresql (I have submitted a few patches for the same).

My preference goes for PostgreSQL also. Performances highly depends on
schema, I don't know for Drupal. A common urban legend says that
PostgreSQL is a lot faster on huge volumetry, and I tend to believe this
is true, if you consider that PostgreSQL is full ACID compliant where
MySQL isn't, so per definition a lot more robust than MySQL for a long
term usage.

Also, PostgreSQL connections consume less RAM than MySQL connections
buffers (may be untrue with PDO, not sure).

And yes, this is quite easy to write standard SQL from MySQL specific
syntax (there are no much left out there).

Pierre.