Help:Installation/General notes

Extension "Semantic MediaWiki"Allows to store and query data annotated to pages has dependencies that will be made available during the installation.
Individual extensions to Semantic MediaWiki, e.g. extension "Semantic Result Formats"Provides additional formats for semantic queries may have different requirements.
Individual extensions to Semantic MediaWiki may not be compatible with the "~4.1" release (yet). Please see those extensions' documentation pages, or contact the respective developers, for further information.
To upgrade an older version of Semantic MediaWiki, be sure to read the relevant section before starting the upgrade.
If you are forced to use MediaWiki < 1.38.x it is recommended to set configuration parameter $wgShellLocale (MediaWiki.org) to C.UTF-8. However, this setting is removed (now obsolete) for recent, supported versions, of MediaWiki >= 1.38.x 1

Please always check the exact requirements and follow the instructions carefully. Make sure you understand the legal disclaimer in the file COPYING before proceeding.
It is required that the PHP mbstring extension is enabled (provides PHP mb_*() multibyte functions such as mb_strpos in the php_mbstring.dll). This is standard but not enabled by default on some distributions of PHP.
It is required that PCRE - Perl Compatible Regular Expressions is at version 8.38 or later.2

When using a SPARQL backend, Semantic MediaWiki and onoi/http-request requires access to the cURL functions of PHP. These functions may have to be enabled/installed to be available.
While not required (yet), it is suggested to have the PHP intl (ICU) extension enabled especially when Semantic MediaWiki is used in a UTF-8 (non-Latin) environment.
For users that require symbolic links, some information can be found here.

For installation and upgrade, Semantic MediaWiki needs the rights to create new tables (CREATE) and to alter tables (ALTER). You can remove both rights after Semantic MediaWiki is set up. The maintenance script "setupStore.php"Allows to set up the data backend/store can use the DB credentials from "LocalSettings.php" for this purpose, avoiding the need of extra rights for the wiki DB user. See also the help page on database privileges, when using SMWSQLStore3.
When using the configuration parameter $smwgDefaultStoreSets the storage backend to be used for the semantic data set to a SQL data backend (default), Semantic MediaWiki creates and alters temporary tables for certain semantic queries. To do this, the wiki's database user account must have privileges for CREATE TEMPORARY TABLES and DROP. If you do not wish to allow such privileges, please read how to disable the use of temporary tables in "LocalSettings.php". See also the help page on database privileges, when using SMWSQLStore3.
Some notes and related settings for a multi-database environment
Webserver notes lists settings or limitations that are imposed by a specific webserver environment

Extended list of recommendations and settings
It is highly recommended to have the parser cache and Semantic MediaWiki specific cache enabled and set to appropriate values.
Information about regular maintenance tasks and the job queue can be found here.

References