PostgreSQL is a powerful, open source object-relational database system running on all major platforms. It supports native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl and ODBC among others.
Features:fully ACID compliant
full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages)
includes most SQL 2008 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP
supports storage of binary large objects, including pictures, sounds, or video
multi-Version Concurrency Control (MVCC)
Highly customisable
CAT is an environment for group coding and analyzing data sets, including computing inter-rater reliability. Users can create a free account, or download the ASP.NET tool suite to run independently.
Software for corpus linguists and text/data mining enthusiasts. The CorpusExplorer combines over 50 interactive visualizations under a user-friendly interface. Routine tasks such as text acquisition, cleaning or tagging are completely automated. The simple interface supports the use in university teaching and leads users/students to fast and substantial results. The CorpusExplorer is open for many standards (XML, CSV, JSON, R, etc.) and also offers its own software development kit (SDK)