connection pool server and replication proxy for PostgreSQL
pgpool is a connection pool server for PostgreSQL, running between
PostgreSQL's client and server. Any PostgreSQL client can connect to
pgpool as if it's a real PostgreSQL server; pgpool caches the
connection to the PostgreSQL server to reduce the overhead involved in
establishing the connection to it. pgpool-II can also be used to
execute queries simultaneously on several servers, that is, "parallel
query" processing. Finally, pgpool can be used for fail over purposes.
If the first server goes down, pgpool will automatically switch to the
secondary server.
