Someone wanted a page of features that PostgreSQL supported that MySQL didn't, so here we go:
|Feature|MySQL 3.x|MySQL 4.0.x|MySQL 4.1.x|PostgreSQL |SubSelects?| No | Limited | Yes | Yes |Views | No | No | No | Yes |Foreign Key relationships | No | Yes | Yes | Yes |Foreign Key constraints | No | No | No | Yes |Triggers | No | No | No | Yes |Indexing on non trivial types | No | No | No | Yes |Sequences | Partial (auto_increment) | Partial (auto_increment) | Partial (auto_increment) | Yes |Transactions | No | Yes | Yes | Yes |OO (Inheritance of tables) | No | No | No | Yes |Async Notifications | No | No | No | Yes |Constraints | No | No | No | Yes |SELECT INTO | No | Yes (INSERT INTO ... SELECT) | Yes (INSERT INTO ... SELECT) | Yes |Stored Procedures | No | No | No | Yes |Row level locking | Yes (with Innodb) | Yes (with Innodb) | Yes (with Innodb) | Yes |Table level locking | Yes | Yes | Yes | Yes |Multiversion Concurrency Control (MVCC) | No | No | No | Yes
Wow, so is there anything that MySQL can do that PostgreSQL can't? -- AlastairPorter
MySQL's big advantage is that it's stupidly simple. If you don't know much about SQL, you can get in and use MySQL and some of the great tools it has (phpMyAdmin!) to do pretty much what you want.
MySQL's big disadvantage is that it's stupidly simple. If you have learnt about SQL, you find out that in MySQL it is very hard to do complicated things, and, if you do try and do complicated things, it bogs down and goes very slow.
In recent studies I've seen (Posted by !UniForum?) MySQL is slightly faster per query, but PostgreSQL can handle more concurrent connections, not that you really care, because if you have that kind of load you really want to be looking at having redundancy and/or a bigger/better database (Oracle?).
MySQL has some nice features like the ability to modify tables schema easily (PostgreSQL won't let you add a new NOT NULL row in one step for example), and doesn't require regular maintenance that PostgreSQL does (you have to regularly VACUUM tables on PostgreSQL if they have a high modification rate), but MySQL is let down by the complete lack of advanced features that you end up needing.
(Actually one just has to do "alter table alter column" to change a column's NULL or DEFAULT attributes)
-- PerryLorier
Look what I found...
http://www-css.fnal.gov/dsg/external/freeware/Repl_mysql_vs_psql.html
Would someone please comment on this one?
I'll give a whirl.
The major reason why mysql is a PITA is that it doesn't support many standard features such as "views" and "subselects". People may scoff that these are "syntactic sugar" but they seriously improve the maintainability of your database, when combined with well thought out constraints you can trust your data to be correct. Mysql is a database that if you do any SQL in for a reasonable length of time you'll quickly reach the limitations of.
There are also plenty of easy to use admin tools for postgres these days including psql, pgAccess, pgAdmin, phpPgAdmin, Tora. With the limitations of MySQL I see no reason to use it except for the future technical chalenge of migrating all the data into a more extendable database.
See also: http://sql-info.de/mysql/gotchas.html for issues to be aware of when using mysql.
the feature was available or not.
http://www.mysql.com/information/features.html
This site has an indepth article on real world performance testing of Mysql and !PostGres?.
4 pages link to PostgresVsMysql: