Foreign Data Wrappers (FDW)¶

In 2003, SQL was expanded to include SQL/MED (SQL Management of External Data). PostgreSQL 9.1 supports this read-only, 9.3 then also write. Since then, a number of Foreign Data Wrappers (FDW) have been developed for PostgreSQL.

The following is just a small selection of the best-known FDWs:

Note

Most of these wrappers are not officially supported by the PostgreSQL Global Development Group (PGDG).

Generic SQL wrappers¶

ODBC

Native ODBC FDW for PostgreSQL ≥9.5

GitHub

Multicorn

Multicorn makes it easy to develop FDWs. For example, SQLAlchemy uses Multicorn to save your data in PostgreSQL.

VirtDB

Native access to VirtDB (SAP ERP, Oracle RDBMS)

GitHub

Specific SQL wrappers¶

postgres_fdw

With postgres_fdw data from other PostgreSQL servers can be accessed.

Oracle

FDW for Oracle databases

MySQL

FDW for MySQL from PostgreSQL≥9.3

GitHub
PGXN

SQLite

FDW for SQLite3

NoSQL database wrappers¶

Cassandra

FDW für Cassandra

Neo4j

FWD for Neo4j, which also provides a cypher function for PostgreSQL

GitHub
Docs

Redis

FDW for Redis

GitHub

Riak

FDW for Riak

GitHub

File wrappers¶

CSV

Official extension for PostgreSQL 9.1

Git
Docs

JSON

FDW for JSON files

XML

FDW for XML files

GitHub
PGXN

Geo wrappers¶

GDAL/OGR

FDW for the GDAL/OGR driver including databases like Oracle and SQLite as well as file formats like MapInfo, CSV, Excel, OpenOffice, OpenStreetMap PBF and XML.