PostgreSQL for Solaris
PostgreSQL for Solaris 10 is the open source enterprise database platform of choice, fully integrated into Solaris 10 with comprehensive support offerings from Sun. PostgreSQL can be easily extended and customized and, with no license fees. It contains support for native DTrace probes, Predictive Self-Healing and Containers. It is reliable and highly available with capabilities such as Multi-Version Currency Control (MVCC), Point-in-Time Recovery and full ACID compliance as well as being Secure-by-Default.

JavaDB
Java DB is Sun's supported distribution of the open source Apache Derby 100% Java technology database. It is fully transactional, secure, easy-to-use, standards-based -- SQL, JDBC API, and Java EE -- yet small, only 2MB. JavaDB is ideal for departmental Java client-server apps, Java app development and testing, embedding in applications, multi-platform use, within browser-based web apps, and the J2ME CDC (i.e. PDA) environment.

MYSQL
CSKamp - The MySQL included in this package is a 32-bit version of MySQL5 with client-side support to work with PHP.

CSKmysql - is a 64bit version of MySQL5 and is built with innodb.