Database FAQ

Note: This article is a work in progress. Please use the page comments or an appropriate moodle.org forum for any recommendations/suggestions for improvement.

There are two types of "databases" in Moodle:

a) The Moodle activity named Database

Database activity module FAQ is the FAQ page

b) The database on your server where Moodle stores all its content

Here is some additional information that may help guide you to more information to answer your FAQs

Database activity module

Moodle Docs

Moodle database

Moodle Docs links

Category:DB
Development:Database schema introduction
Development:Database Schema - The files available here are in DBDesigner 4 format.

DBDesigner 4 is a schema drawing program for MySQL data bases released under GPL.

Create Moodle site database

Moodle Forums links

Databases forum
"Moodle database design issues I'd like to tackle/see tackled" in the Moodle forum (from 2007).
MySQL workbench file for download (for using with MySQL Workbench). - Related forum discussion: Referential integrity in Moodle

Non Moodle.org links

"Database abstraction layers and Moodle" from Christopher Douce's blog (Open University)

Moodle core libraries

Moodle's core libraries provide lots of functions for working with the database.

/lib/datalib.php for higher level functions
/lib/dmllib.php for lower level functions

XMLDB

XMLDB stores the database definition in an XML format that can be used to install Moodle on any database.

Introduction to Moodle Programming course:

Different kinds of databases

New database layer in Moodle 2.0

See Development:DB_layer_2.0.
For new features in Moodle 2.0 see Development:Coding#Database.
Delegated transactions on Moodle Docs and the related forum discussion on Database transactions in Moodle

Documentation