Enabling and configuring full-text search

Table of Contents

Full-text search for SQL (MySQL, MariaDB or SQLite) is not enabled by default since it is still considered experimental. Follow the following steps to enable, configure and fine-tune this feature on your wiki.

Check the requirements

• Support was added for MySQL/MariaDB1 and SQLite2 while PostgreSQL34 is currently not supported.
• Only SMWSQLStore3 is supported since the SPARQLStore would require the native support of full-text search capabilities by the triple-store.

• Semantic MediaWiki 2.5.0+
• SMWSQLStore3 using MySQL 5.5+1, MariaDB 10.0.5+1 or SQLite 3.8+2
• PHP 5.5+

Enable

To make full-text search available on your wiki, set Configuration parameter $smwgEnabledFulltextSearchSets whether full-text search support for properties may be used (default: false) to true.

$smwgEnabledFulltextSearch = true;

Configure

• Configuration parameter $smwgFulltextDeferredUpdateSets the number of expected full-text search index updates − Allows to throttle the number of expected index updates
• Configuration parameter $smwgFulltextSearchTableOptionsSets the full-text search table options to use during installation or update − Allows to set database related options
• Configuration parameter $smwgFulltextSearchMinTokenSizeSets the minimum word/token length to help to decide whether MATCH or LIKE operators are to be used for a condition statement − Allows to describe the minimum word/token
• Configuration parameter $smwgFulltextLanguageDetectionSets which languages to detect for the full-text search from an indexable text − Allows to detect a language (experimental setting)
• Configuration parameter $smwgFulltextSearchIndexableDataTypesSets which datatypes are allowed to be indexed using the full-text search − Allows to list datatypes that should be indexed
• Configuration parameter $smwgFulltextSearchPropertyExemptionListSets the property keys for which value assignments are being exempted from the full-text indexing − Allows to list properties that should be not be indexed
• If the SMW_FIELDT_CHAR_NOCASE option to configuration parameter $smwgFieldTypeFeaturesSets relational database specific field type features is enabled the full-text search only comes into effect for selections using the comparators ~ and !~.5

Update the database indexes

The next step is to run maintenance script "rebuildFulltextSearchTable.php"Allows to rebuild the full text search data table. This will create the necessary table for special full-text index operations.

Continue here for detailed instructions on how to do indexing.

Keep the database in shape

It is recommended to set up a cronjob to run rebuildFulltextSearchTable on a regular basis. Note also that changes to any of the above settings requires to re-run maintenance script "rebuildFulltextSearchTable.php"Allows to rebuild the full text search data table.