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FlockDB is a distributed graph database for storing adjancency lists.


Last Week downloads: 4
Total downloads: 258
  • Last Updated: Jan 18, 2011
  • License: GPL Free
  • OS: Unix/Linux
  • Requirements: JDK 1.6 or higher & sbt 0.7.4 or higher & thrift 0.2.0 or higher

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4 out of 5 based on 1 ratings for FlockDB

For FlockDB Publisher's description


FlockDB is a Development software developed by Twitter. After our trial and test, the software is proved to be official, secure and free. Here is the official description for FlockDB:

FlockDB is a distributed graph database for storing adjancency lists, with goals of supporting:

a high rate of add/update/remove operations
potientially complex set arithmetic queries
paging through query result sets containing millions of entries
ability to "archive" and later restore archived edges
horizontal scaling including replication
online data migration
Non-goals include:

multi-Hop queries (or graph-walking queries)
automatic shard migrations
FlockDB is much simpler than other graph databases such as neo4j because it tries to solve fewer problems. It scales horizontally and is designed for on-line, low-latency, high throughput environments such as web-sites.

Twitter uses FlockDB to store social graphs (who follows whom, who blocks whom) and secondary indices. As of April 2010, the Twitter FlockDB cluster stores 13+ billion edges and sustains peak traffic of 20k writes/second and 100k reads/second.

It does what?
If, for example, you're storing a social graph (user A follows user B), and it's not necessarily symmetrical (A can follow B without B following A), then FlockDB can store that relationship as an edge: node A points to node B. It stores this edge with a sort position, and in both directions, so that it can answer the question "Who follows A?" as well as "Whom is A following?"

This is called a directed graph. (Technically, FlockDB stores the adjacency lists of a directed graph.) Each edge has a 64-bit source ID, a 64-bit destination ID, a state (normal, removed, archived), and a 32-bit position used for sorting. The edges are stored in both a forward and backward direction, meaning that an edge can be queried based on either the source or destination ID.

For example, if node 134 points to node 90, and its sort position is 5, then there are two rows written into the backing store:

forward: 134 -> 90 at position 5
backward: 90 <- 134 at position 5
you can free download FlockDB now.


Please be aware that Brothersoft do not supply any crack, patches, serial numbers or keygen for FlockDB,and please consult directly with program authors for any problem with FlockDB.