New port: databases/postgresql-cstore_fdw

Cstore_fdw is a extension of PostgreSQL. This extension uses the Optimized Row
Columnar (ORC) format for its data layout. ORC improves upon the RCFile format
developed at Facebook, and brings the following benefits:

• Compression: Reduces in-memory and on-disk data size by 2-4x. Can be

	  extended to support different codecs.

• Column projections: Only reads column data relevant to the query.

	  Improves performance for I/O bound queries.

• Skip indexes: Stores min/max statistics for row groups, and uses them

	  to skip over unrelated rows.

Further, cstore_fdw used the Postgres foreign data wrapper APIs and type
representations with this extension. This brings:

• Support for 40+ Postgres data types. The user can also create new types

	  and use them.

• Statistics collection. PostgreSQL's query optimizer uses these stats to

	  evaluate different query plans and pick the best one.

• Simple setup. Create foreign table and copy data. Run SQL.

WWW: https://github.com/citusdata/cstore_fdw

PR: 219635
Submitted by: Jov <amutu@amutu.com>