Potentially raising the bar on SQL scalability, Facebook has released as open source a SQL query engine it developed called Presto that was built to work with petabyte-sized data warehouses. Currently, over 1,000 Facebook employees use Presto daily to run 30,000 interactive queries, involving over a petabyte of processing, according to a post authored by Facebook software engineer Martin Traverso. The company has scaled the software to run on a 1,000 node cluster.