Re: [HACKERS] What can we learn from MySQL?

Hi!

Tim Conrad wrote:
> I was researching an article I wrote about a comparison between
> Postgres and MySQL recently (If you want, you can read the article
> at http://www.devx.com/dbzone/Article/20743/). I noticed some clear
> differences between the mysql.com website and the Postgres website.

Sorry, couldn't resist: may I suggest doing the research *before*
writing an article, not *after*?

My favourite part of it is:
--------
MySQL uses traditional row-level locking. PostgreSQL uses something
called Multi Version Concurrency Control (MVCC) by default. MVCC is a
little different from row-level locking in that transactions on the
database are performed on a snapshot of the data and then serialized.
New versions of PostgreSQL support standard row-level locking as an
option, but MVCC is the preferred method.
--------

> 2) There doesn't seem to be a clear roadmap on Postgres features.
> When certian things are expected. There's the TODO list that
> Bruce maintains, but it only outlines 'near' fixes. MySQL has a
> nice listing of what to expect in certian future versions. I know
> it's not a perfect list, but it'd be nice to know when full blown
> replication will be included in PostgreSQL as an example.

MySQL's roadmap is complete bullshit. Subselects were first promised in
4.0, which was "not that far away" [1] back in 1998! Well, they are in
4.1, which is still alpha in 2004.

Of course, some gullible people actually believe this and compare [2]
the existing and working implementations with vaporware (MySQL 5.1,
anyone?).

> On those same lines, there doesn't seem to be anything about the
> improvements in the minor versions. It seems that in every
> release (i.e. 7.2,7.3,7.4) there are pretty significant changes,
> but finding a place that outlines these changes is somewhat
> difficult.

Have you tried looking in the release notes [3]?

[1] http://www.geocrawler.com/archives/3/194/1998/8/0/1061364/
[2] http://www.devx.com/dbzone/Article/20743/1763?supportItem=1
[3] http://www.postgresql.org/docs/7.4/interactive/release.html