key/value database library
Tokyo Cabinet, developed as the successor of QDBM, is a library of routines for managing a simple file-based key/value database. Keys and values are serial bytes with variable length; both binary data and character string can be used as key or value. Data are organized in a hash table, B+ tree, or fixed-length array. There is no concept of data tables or data types.
Homepage: http://fallabs.com/tokyocabinet/