Where is mediawiki database

To avoid swamping the primary server every time the replicas lag, use of this approach should be kept to a minimum. In most cases you should just read from the replica and let the user deal with the delay. Due to the high write rate on Wikipedia and some other wikis , MediaWiki developers need to be very careful to structure their writes to avoid long-lasting locks. By default, MediaWiki opens a transaction at the first query, and commits it before the output is sent.

Locks will be held from the time when the query is done until the commit. So you can reduce lock time by doing as much processing as possible before you do your write queries. Often this approach is not good enough, and it becomes necessary to enclose small groups of queries in their own transaction. Use the following syntax:. Use of locking reads e. They are poorly implemented in InnoDB and will cause regular deadlock errors.

It's also surprisingly easy to cripple the wiki with lock contention. Then use the affected row count to see if the query succeeded. Don't forget about indexes when designing databases, things may work smoothly on your test wiki with a dozen of pages, but will bring a real wiki to a halt. See above for details. However, primary keys spanning over more than one field should be included in the main table definition:.

For extension patches, use the extension's equivalent of these files. Translate this page. Other languages:. Oracle SQL Server. Schema tables API property associations Field prefixes Primary key storage in other fields Wikimedia extension tables.

Settings Sharing. Category : Database. Namespaces Manual Discussion. Views Read View source View history. You will then get a new DB with exactly the same content, which you had before. Then copy all your old MediaWiki files in place including LocalSettings. If you have changed the MySQL username, password or host, adjust these and things should be going. This post was posted by Thanks for your prompt answer. OK, let me take the issues one by one.

Yes, I used the installer. I am not aware of a change of prefix, but that is probably what I have done besides selecting a different language as the Wiki language. The backup is a complete set of MySQL database files.

The new Mediawiki is of a different version, so some of the old tables generate errors. Query-Killer only runs when replication lag replag is noticeable and kills queries based on how long they have been running. If and when Query-Killer kills a query depends on the actual database replication lag.

See the following table. Sometimes, you might want to artificially restrict the runtime of a query. This is useful for web tools, where you want to restrict the runtime of a query and present an error to the user if it runs too long.

Rather than allowing the connection to time out, or the user to get bored and go away. It can also be used to limit execution time of a query which is usually fast, but sometimes runs for longer than desired.

If connecting using the command line 'mysql' tool, comments are not passed to the server by default, and so will not be visible to the query killer. Use the '-c' flag when connecting to suppress this behaviour. A possibly out of date description of the schema is available at Manual:Database layout. Page content itself is not available in the database. WikiProxy may be useful as well. The toolserver meta- database is a database called "toolserver", containing information about other databases on the toolserver.

It can be read by anyone and is available on all database servers. The host name of the primary copy is sql-toolserver.

The toolserver database is updated automatically on a daily basis. This table contains the primary namespace names for the wikis in the wiki table. Use of this table is deprecated, use the namespacename table instead, which covers all valid names for each namespace in each wiki, not just the primary names. The variable should have some documentation there. See also: Manual:Mime type detection. See also: Manual:Configuring file uploads. They apply to caching using Varnish as well as Squid.

The following setting is no longer used in supported versions of MediaWiki, but still exists for backward compatibility. Tidy is an open source tool that cleans up broken HTML.