conikost@gentoo.org Conrad Kostecki HypoPG/hypopg HypoPG is a PostgreSQL extension adding support for hypothetical indexes. A hypothetical - or virtual - index is an index that doesn't really exist, and thus doesn't cost CPU, disk or any resource to create. They're useful to know if specific indexes can increase performance for problematic queries, since you can know if PostgreSQL will use these indexes or not without having to spend resources to create them.