Tera
An Internet-scale database
...Besides, Tera is widely used in many Baidu products with varied demands, which range from throughput-oriented applications to latency-sensitive services, including web indexing, WebPage DB, LinkBase DB, etc. Tera is the collection of many sparse, distributed, multidimensional tables. The table is indexed by a row key, column key, and a timestamp; each value in the table is an uninterpreted array of bytes. Support RAMDISK/SSD/DFS tiered cache. Block cache and Bloom Filters for real-time queries. Multi-type table support (RAMDISK/SSD/DISK table). Easy to use C++/Java/Python/REST-ful API. ...