# Mroonga User-Defined Functions

- [Creating Mroonga User-Defined Functions](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/creating-mroonga-user-defined-functions.md): Instructions on how to manually create Mroonga's UDFs if they were not automatically installed, ensuring full functionality.
- [last\_insert\_grn\_id](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/last_insert_grn_id.md): This UDF returns the unique ID assigned by Groonga for the last inserted record, useful for tracking internal record identifiers.
- [mroonga\_command](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_command.md): Execute raw Groonga commands directly from MariaDB using this UDF, allowing for advanced administration and inspection of the Groonga database.
- [mroonga\_escape](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_escape.md): This function escapes special characters in a string to make it safe for use in Mroonga full-text search queries.
- [mroonga\_highlight\_html](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_highlight_html.md): Highlight keywords within a text string using HTML tags, making it easy to display search results with matched terms emphasized.
- [mroonga\_normalize](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_normalize.md): This UDF normalizes a given string using Groonga's normalizers, ensuring consistent text processing for accurate indexing and searching.
- [mroonga\_snippet](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_snippet.md): This function extracts a snippet of text surrounding a keyword from a document, providing necessary context for search result displays.
- [mroonga\_snippet\_html](https://mariadb.com/docs/server/server-usage/storage-engines/mroonga/mroonga-user-defined-functions/mroonga_snippet_html.md): Similar to mroonga\_snippet, this function generates HTML-formatted snippets, automatically wrapping matched keywords in tags for web display.


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