BRIN indexes on geospatial database
BRINs (Block Range INdexes) are one of the major new features introduced with PostgreSQL 9.5. They allow to directly select just blocks of table pages needed for queries execution, resulting on smaller indexes that can be easily contained in memory and that require less maintenance than the existing ones.
These features make BRIN particularly suitable for very large tables, and more in general for query with a low-selectivity that would be executed preferring a sequential scan of all tables blocks instead of using indexes.
Many examples of BRIN usage for numeric and string searches on PostgreSQL databases can be found in the web: in this presentation I'm going to explain how BRIN can be efficiently used for searches of geometric objects in geospatial database, highlighting the performance increase compared to the other indexes type.