The first development release of MySQL Version 4.1 is available at no cost at http://www.mysql.com and integrates improvements that enhance the MySQL architectural foundation for building heavy-load commercial applications.
MySQL said the database could be used by developers and it may still make small improvements during the next few months.
Included is support for SQL sub-selects, also known as sub-queries or nested queries, which enable users to search complex data. Users can achieve query consolidation by nesting one query inside another to build a resource otherwise unavailable for searching in a single statement.
Sub-selects enable users to query within a result set, limit the result set, or correlate results with an otherwise-unrelated query in a single call to the database.
Also featured in Version 4.1 is a highly optimised MySQL server library with a smaller footprint that performs faster when embedded in third-party software.
SSL (Secure Socket Layer) support is improved in Version 4.1, in which the "mysql" server process can use SSL to secure traffic to MySQL databases from origination points such as a Windows application residing outside a firewall.
Version 4.1 also supports as many as 64Gbyte of memory in 32-bit Windows (AWE memory) using the InnoDB storage engine. Performance is improved through in-memory tables using B-TREE indices.
Also available in Version 4.1 is support for Unicode through the UCS2 and UTF8 international character sets, for easier storage and manipulation of internationalised data. Support also is included for a subset of GIS data types as proposed by the OpenGIS consortium, for searching in maps.
MySQL also provided some details on the next major version of the database, Version 5.0, which is due by the end of the year. It will include features such as stored procedures and triggers.
Sun Microsystems has been bundling MySQL with its LX50 Linux server.