Re: Differentiating different Open Source databases

On Mon, May 16, 2011 at 3:09 AM, Dimitri Fontaine
<dimitri(at)2ndquadrant(dot)fr> wrote:
> you only get so far with Oracle and MySQL.

Disclaimer: I do not speak for any of my employers, past, present or future.

"only get so far with... MySQL", so, yeah, about that... You are wrong.

Last I heard, it was the primary persistent data store for the worlds
largest social network. A system that several hundreds of million
people interact with on a daily basis.

Last I heard, it was also the primary persistent data store for the
worlds largest web hosting provider, domain registrar and SSL
registrar.

Last I heard, it was also the primary persistent data store for the
largest ad network (with billions in revenue) on the web. From
personal experience this is not the only place MySQL is used with
financial data.

A question I have asked numerous times in the last year is "Does
anyone run a farm with more than 1,000 Postgres servers?". The answer
I have received again and again is no. That is not the case with
MySQL. Given the cost of large farms of server, have no doubt that if
PG was a better solution* it would be used. At this point MySQL has
and PG does not have covering indexes, index change buffering, a cheap
optimizer which can be made almost free with hints, on disk
compression, query caching (as a stopgap for Memcache integration),
etc... And for many workloads PG is a better options than MySQL.

And let us not ignore the advantages of on disk checksums. Can anyone
really say that PG cares about your data and MySQL does not while PG
still allows silent corruption? Given the unreliability of SATA drives
this is a real problem.

Whatever your feelings about MySQL, "only get so far" is
intellectually dishonest.

As for NoSQL, that is several families of problems and solutions:
Easy of use - Couch
Caching - Memcache, Redis
Optimizing writes over reads - HBase

The only one where I think PG might beat MySQL is caching with
unlogged tables (a as of yet unreleased feature), and that is assuming
that you don't need to read from them. With a read/write workload I am
not sure who would win in terms of performance, but I doubt that the
difference would be enough to set aside the advantages of
institutional momentum.

Of course, this is all open for debate but is another attempt to say
"PG rocks, MySQL sucks" really worth attempting? It had been tried
more than a few times before and been a losing effort. Are there not
other ways that PG people can spend their time and be more highly
leveraged? Are there not more than enough expensive, difficult to use,
proprietary solutions to pick off and devour before an elephant goes
to sea to try to kill a dolphin? I suggest finding some other db
(particularly a proprietary one) to be your tusk'ing bag, the dolphin
can give as good as it gets. Or better yet, do something really useful
and write tutorials.

*I think that finding people with experience is what is holding PG
back far more than any technical deficiencies. However awesome a piece
of software is, it is worthless if it is impossible to find anyone to
run it.

Best,

Rob "the MySQL guy that really likes PG, except when PG people say
silly things" Wultsch
wultsch(at)gmail(dot)com