About Mroonga

Mroonga is a full text search storage engine based on Groonga, which is an open-source CJK-ready (Chinese, Japanese, and Korean) fulltext search engine using column base. See http://groonga.org for more.

With Mroonga, you can have a CJK-ready full text search feature, and it is faster than the MyISAM and InnoDB full text search for both updating and searching.

Mroonga also supports Groonga's fast geolocation search by using MariaDB's geolocation SQL syntax.

Mroonga currently only supports Linux x86_64 (Intel64/AMD64).

How to Install

Enable Mroonga with the following statement:

INSTALL SONAME 'ha_mroonga';

On Debian and Ubuntu mroonga engine will be installed with

sudo apt-get install mariadb-plugin-mroonga

See Plugin overview for details on installing and uninstalling plugins.

SHOW ENGINES can be used to check whether Mroonga is installed correctly:

SHOW ENGINES;
...
*************************** 8. row ***************************
      Engine: Mroonga
     Support: YES
     Comment: CJK-ready fulltext search, column store
Transactions: NO
          XA: NO
  Savepoints: NO
...

Once the plugin is installed, add a UDF (User-Defined Function) named "last_insert_grn_id", that returns the record ID assigned by groonga in INSERT, by the following SQL.

mysql> CREATE FUNCTION last_insert_grn_id RETURNS INTEGER SONAME 'ha_mroonga.so';

Limitations

• The maximum size of a single key is 4096 bytes.
• The maximum size of all keys is 4GB.
• The maximum number of records in a fulltext index is 268,435,455
• The maximum number of distinct terms in a fulltext index is 268,435,455
• The maximum size of a fulltext index is 256GB

Note that the maximum sizes are not hard limits, and may vary according to circumstance.

For more details, see http://mroonga.org/docs/reference/limitations.html.

Available Character Sets

Mroonga supports a limited number of character sets. These include:

• ASCII
• BINARY
• CP932
• EUCJPMS
• KOI8R
• LATIN1
• SJIS
• UJIS
• UTF8
• UTF8MB4

More Information

Further documentation for Mroonga can be found at http://mroonga.org/docs/