sqlite_fdw

sqlite_fdw : SQLite Foreign Data Wrapper

Overview

Packages

Source

pig build pkg sqlite_fdw;		# build rpm/deb

Install

Make sure PGDG repo available:

pig repo add pgdg -u    # add pgdg repo and update cache

Install this extension with pig:

pig install sqlite_fdw;		# install via package name, for the active PG version

pig install sqlite_fdw -v 18;   # install for PG 18
pig install sqlite_fdw -v 17;   # install for PG 17
pig install sqlite_fdw -v 16;   # install for PG 16
pig install sqlite_fdw -v 15;   # install for PG 15
pig install sqlite_fdw -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION sqlite_fdw;

Usage

sqlite_fdw: SQLite Foreign Data Wrapper

Create Server

CREATE EXTENSION sqlite_fdw;

CREATE SERVER sqlite_server FOREIGN DATA WRAPPER sqlite_fdw
  OPTIONS (database '/path/to/database.db');

Server Options: database (required, path to SQLite file), updatable (default true), truncatable (default false), keep_connections (default true), batch_size (default 1), force_readonly (default false).

No CREATE USER MAPPING is required since SQLite has no authentication model.

Create Foreign Table

CREATE FOREIGN TABLE remote_data (
  id integer OPTIONS (key 'true'),
  name text,
  created timestamp OPTIONS (column_type 'INT'),
  data bytea
)
SERVER sqlite_server
OPTIONS (table 'data_table');

Table Options: table (SQLite table name if different from PostgreSQL name), updatable, truncatable, batch_size.

Column Options: column_name (map to different SQLite column name), column_type (SQLite affinity: INT for epoch timestamps, BLOB for UUIDs), key (mark as primary key for UPDATE/DELETE).

CRUD Operations

SELECT * FROM remote_data WHERE id > 100;
INSERT INTO remote_data (id, name) VALUES (1, 'test');
UPDATE remote_data SET name = 'updated' WHERE id = 1;
DELETE FROM remote_data WHERE id = 1;

Import Foreign Schema

IMPORT FOREIGN SCHEMA public
  FROM SERVER sqlite_server INTO local_schema;

Import Options: import_default (default false), import_not_null (default true).

Data Type Mapping

Timestamps can be stored as TEXT (ISO format) or INT (Unix epoch, use column_type 'INT'). UUIDs can be stored as TEXT (36 chars) or BLOB (16 bytes). The SQLite database file must be readable (and writable for DML) by the PostgreSQL OS user.