EJDB is an embedded JSON database engine. It aims to be a fast MongoDB-like NoSQL library that can be embedded into C/C++/Nodejs/Python3/Lua applications. It features collection-level write locking, collection level transactions, string token matching queries, and a Node.js binding.
The psycogreen package makes it possible for psycopg2 to work with coroutine libraries, using asynchronous calls internally but offering a blocking interface so that regular code can run unmodified. While Psycopg offers coroutine support, the main module is a C extension that cannot be monkey-patched to become coroutine-friendly. Instead it exposes a hook that coroutine libraries can use to install a function integrating with their event scheduler. Psycopg will call the function whenever it executes a libpq call that may block. psycogreen is a collection of "wait callbacks" that can be used to integrate Psycopg with different coroutine libraries. psycogreen is currently mainly useful for integration with gevent.
Tickets MDB is a Web-based personnel/membership database mainly aimed at voluntary organisations but applicable to any operation which needs to register member details and store member training records, abilities, equipment, vehicles, and clothing. It is based on TicketsCAD and allows integration to that platform for sharing of information with Tickets CAD as an operational dispatch system (However, Tickets MDB does not require Tickets CAD to function and is a standalone application in its own right.) Tickets MDB supports mapping of personnel locations using Open Streetmap and Open Layers and allows local storage of map images/tiles so it can work in a non-network environment (with the exception of email to members, which will require a network connection).
Sirix is a versioned tree-based storage system. It provides Snapshot Isolation through MVCC and is best suited for flash-based storage. The tree encoding is suited for heavy update operations. It provides diffing algorithms either to import diffs between currently shredded (imported) XML documents to update a tree structure or to get the differences between versions of a tree structure. A GUI provides several visualizations for comparing imported tree structures.
PixSteward downloads pictures and metadata from your Flickr accounts and archives them in a relational database on your computer, allowing offline searches and image exporting. With PixSteward, you can safely back up multiple Flickr photostreams with metadata to your Mac, perform sophisticated searches (even where there's no Internet connection), rapidly browse your picture archive and export original-sized JPEGs, PNGs, and GIFs (groups and one-by-one), export sets of pictures along with their metadata for use in other apps, and edit your Flickr tags, titles, and descriptions simultaneously on Flickr and within PixSteward.
The YB.ORM library aims to simplify writing C++ code that has to deal with SQL databases. The goal is to provide a convenient interface like SQLAlchemy (Python) or Hibernate (Java). The library itself is cross-platform and supports a variety of SQL dialects: SQLite3, MySQL, Postgres, Oracle, and Firebird. Integration with Boost, Qt4, and wxWidgets is built-in. In a typical usage scenario, you would describe your database schema and table relationships in a simple XML-based format, generate SQL code to populate database schema with tables, generate C++ classes, add application-specific logic to the classes, and use these classes in cooperation with the Session object to query objects from the database, create new or modify/delete existing objects, or link and unlink objects using relations. Simple serialization to XML is supported along with connection pooling.
Groonga is a fast and accurate full text search engine based on an inverted index. Newly registered document instantly appears in search results, and updates are allowed without read locks. These characteristics result in superior performance for real-time applications. It is also a column-oriented database management system (DBMS). Compared with well-known row-oriented systems, such as MySQL and PostgreSQL, column-oriented systems are more suited for aggregate queries.