From AdminWiki

Contents 1 SQL 1.1 MySQL 1.2 PostgreSQL 1.3 Oracle 2 LDAP 3 Footnotes

SQL

MySQL

Database that has a SQL interface. Claims to be ACID^[1] -compliant; tries hard to. Same story as with PHP: Large availability, everybody uses it, hardly the best choice.

Food for thought:

• MySQL Gotchas
• MySQL oddities
• MySQL Sucks
• MySQL sucks
• MySQL subselects suck

PostgreSQL

Full-featured SQL Server. Is ACID^[1] -compliant. Needs more maintenance than MySQL. Doesn't have native replication support.

Food for thought:

• PostgreSQL gotchas

Oracle

The commercial behemoth.

LDAP

LDAP systems are like Databases too - often they build on a generic database and provide a more specialised view.

• OpenLDAP/slapd: the open source LDAP daemon
• Novell eDirectory/NLDAP: a commercial system

Footnotes

1. ↑ ^1.1 1.2 Atomicity, Consistency, Isolation, Durability. See The ACID model