Faster subqueries in MariaDB
The developers of the free database say that version 5.3 of MySQL fork MariaDB mainly speeds up the execution of queries. Subqueries in particular are said to be faster: wherever possible, the query planner replaces this type of query with
JOINs. In addition, the server stores optimised subqueries in a cache.
Other optimisations concern derived tables, subqueries in the
FROM clause of a
SELECT statement and materialised
VIEWs. For instance, MariaDB generates its own key for accessing these objects in order to accelerate access. Multi-range reads, where large parts of the index are queried at once, are also said to be faster.
The code in MariaDB 5.3 still generally corresponds with MySQL 5.1; the changes introduced in MySQL 5.5 are expected to be included in MariaDB 5.5. Performance improvements from MariaDB 5.5 on Windows have also been backported to MariaDB 5.3.
Further details on the MariaDB 5.3 Beta release are available in the release notes and it can be downloaded for Windows (32-bit and 64-bit), Solaris and Linux (64-bit, 32-bit, Centos RPMs and RHEL RPMS), or as source.