Skip to content
PostgreSQL driver and toolkit for Go
Go Shell
Branch: master
Clone or download
Latest commit 366c926 Jan 25, 2020
Type Name Latest commit message Commit time
Failed to load latest commit information.
examples Fix typo in README Sep 30, 2019
internal/sanitize Restore simple protocol support May 21, 2019
log Add context.Context to Logger interface Aug 3, 2019
pgxpool Add a couple error checks Nov 22, 2019
stdlib Fixes #664 -- implement DriverContext for stdlib Jan 23, 2020
travis Update and simplify test instructions May 25, 2019
.gitignore Use environment variables for test configuration Dec 31, 2018
.travis.yml Add PG 12 to Travis test matrix Dec 23, 2019 Update changelog Jan 24, 2020
LICENSE Readme: update pkg paths for pgtype & pgmock Oct 13, 2019
batch.go Add docs regarding closing BatchResults Sep 20, 2019
batch_test.go Add test for larger batches Oct 12, 2019
bench_test.go Remove QueryArgs Sep 2, 2019
conn.go Add arguments count check to execParamsAndPreparedPrefix Jan 4, 2020
conn_test.go Add arguments count check to execParamsAndPreparedPrefix Jan 4, 2020
copy_from.go Make Conn.ConnInfo private Sep 10, 2019
copy_from_test.go Make Conn.ConnInfo private Sep 10, 2019
doc.go Fix some typos Sep 4, 2019
example_custom_type_test.go Make Conn.ConnInfo private Sep 10, 2019
example_json_test.go Fix go modules Apr 20, 2019
extended_query_builder.go Move the second part of the nil check earlier in the function. This f… Oct 3, 2019
go.mod Update pgconn to 1.3.0 Jan 24, 2020
go.sum Update pgconn to 1.3.0 Jan 24, 2020
go_stdlib.go Support nil pointers to value implementing driver.Valuer Oct 27, 2017
helper_test.go Require conn and pool configs to be created by ParseConfig Aug 24, 2019
large_objects.go Fix large objects functionality when PreferSimpleProtocol = true Dec 27, 2019
large_objects_test.go Fix large objects functionality when PreferSimpleProtocol = true Dec 27, 2019
logger.go Add context.Context to Logger interface Aug 3, 2019
messages.go Use pgproto3.FieldDescription instead of pgx version May 4, 2019
pgbouncer_test.go Rename PreparedStatementCache to StatementCache Aug 25, 2019
query_test.go fix: Fix typo Jan 25, 2020
rows.go Add Rows.Values support for unknown types Jan 24, 2020
tx.go fix: Fix typo Jan 25, 2020
tx_test.go Fix dbSavepoint.Begin recursive self call Oct 23, 2019
values.go Refactor format code choosing Aug 25, 2019
values_test.go Make Conn.ConnInfo private Sep 10, 2019

Build Status

pgx - PostgreSQL Driver and Toolkit

pgx is a pure Go driver and toolkit for PostgreSQL. The driver part of pgx is compatible with database/sql but also offers a native interface similar in style to database/sql that offers better performance and more features.

The toolkit part is a related set of packages that implement PostgreSQL functionality such as parsing the wire protocol and type mapping between PostgreSQL and Go. These underlying packages can be used to implement alternative drivers, proxies, load balancers, logical replication clients, etc.

The current release of pgx v4 requires Go modules. Checkout and vendor branch v3 to use the previous version.

Example Usage

package main

import (


func main() {
	conn, err := pgx.Connect(context.Background(), os.Getenv("DATABASE_URL"))
	if err != nil {
		fmt.Fprintf(os.Stderr, "Unable to connection to database: %v\n", err)
	defer conn.Close(context.Background())

	var name string
	var weight int64
	err = conn.QueryRow(context.Background(), "select name, weight from widgets where id=$1", 42).Scan(&name, &weight)
	if err != nil {
		fmt.Fprintf(os.Stderr, "QueryRow failed: %v\n", err)

	fmt.Println(name, weight)

Choosing Between the pgx and database/sql Interfaces

It is recommended to use the pgx interface if the application is only targeting PostgreSQL and no other libraries that require database/sql are in use. The pgx interface is faster and exposes more features.

The database/sql interface only allows the underlying driver to return or receive the following types: int64, float64, bool, []byte, string, time.Time, or nil. The only way to handle other types is to implement the database/sql.Scanner and the database/sq/driver.Valuer interfaces. These interfaces require using the text format for transmitting values. The binary format can be substantially faster, and that is what the pgx native interface uses to encode and decode values for PostgreSQL.


pgx supports many additional features beyond what is available through database/sql.

  • Support for approximately 60 different PostgreSQL types
  • Automatic statement preparation and caching
  • Batch queries
  • Single-round trip query mode
  • Full TLS connection control
  • Binary format support for custom types (can be much faster)
  • Copy protocol support for faster bulk data loads
  • Extendable logging support including built-in support for log15, logrus, zap, and zerolog
  • Connection pool with after connect hook to do arbitrary connection setup
  • Listen / notify
  • PostgreSQL array to Go slice mapping for integers, floats, and strings
  • Hstore support
  • JSON and JSONB support
  • Maps inet and cidr PostgreSQL types to net.IPNet and net.IP
  • Large object support
  • NULL mapping to Null* struct or pointer to pointer
  • Supports database/sql.Scanner and database/sql/driver.Valuer interfaces for custom types
  • Notice response handling (this is different than listen / notify)
  • Simulated nested transactions with savepoints


There are three areas in particular where pgx can provide a significant performance advantage over the standard database/sql interface and/or other drivers.

  1. PostgreSQL specific types - Types such as arrays can be parsed much quicker because pgx uses the binary format.
  2. Automatic statement preparation and caching - pgx will prepare and cache statements by default. This can provide an significant free improvement to code that does not explicitly use prepared statements. Under certain workloads it performs nearly 3x the queries per second.
  3. Batched queries - Multiple queries can be batched together to minimize network round trips.

Related Libraries

pgx is the head of a family of PostgreSQL libraries. Many of these can be used independently. Many can also be accessed from pgx for lower-level control.

pgconn is a lower-level PostgreSQL database driver that operates at nearly the same level as the C library libpq.

pgxpool is a connection pool for pgx. pgx is entirely decoupled from its default pool implementation. This means pgx can be used with a different pool or without any pool at all.

database/sql compatibility layer for pgx. pgx can be used as a normal database/sql driver, but at any time the native interface may be acquired for more performance or PostgreSQL specific functionality.

Over 70 PostgreSQL types are supported including uuid, hstore, json, bytea, numeric, interval, inet, and arrays. These types support database/sql interfaces and are usable even outside of pgx. They are fully tested in pgx and pq. They also support a higher performance interface when used with the pgx driver.

pgproto3 provides standalone encoding and decoding of the PostgreSQL v3 wire protocol. This is useful for implementing very low level PostgreSQL tooling.

pglogrepl provides functionality to act as a client for PostgreSQL logical replication.

pgmock offers the ability to create a server that mocks the PostgreSQL wire protocol. This is used internally to test pgx by purposely inducing unusual errors. pgproto3 and pgmock together provide most of the foundational tooling required to implement a PostgreSQL proxy or MitM (such as for a custom connection pooler).

tern is a stand-alone SQL migration system.

Comparison With Alternatives

For prepared queries with small result sets of simple data types all drivers perform similarly. If prepared statements are not being explicitly used, pgx can have a significant performance advantage due to automatic statement preparation. pgx also can perform better when using PostgreSQL specific data types or query batching. See go_db_bench for some database driver benchmarks.

Another significant difference between the drivers is features and API style.

pq is exclusively used with database/sql. go-pg does not use database/sql at all. pgx supports database/sql as well as its own interface.

go-pg includes many features that traditionally sit above the database driver such as an ORM, struct mapping, soft deletes, schema migrations, and sharding support baked in. pgx does not and will not include such features in the core package.


pgx tests need a PostgreSQL database. It will connect to the database specified in the PGX_TEST_DATABASE environment variable. The PGX_TEST_DATABASE environment variable can be a URL or DSN. In addition, the standard PG* environment variables will be respected. Consider using direnv to simplify environment variable handling.

Example Test Environment

Connect to your PostgreSQL server and run:

create database pgx_test;

Connect to the newly created database and run:

create domain uint64 as numeric(20,0);

Now you can run the tests:

PGX_TEST_DATABASE="host=/var/run/postgresql database=pgx_test" go test ./...

In addition there are tests specific for PgBouncer that will be run if the PGX_TEST_PGBOUNCER_CONN_STRING is set.

Version Policy

pgx follows semantic versioning for the documented public API on stable releases. v4 is the latest stable major version.

You can’t perform that action at this time.