github.com/lib/pq

pq is a Go PostgreSQL driver for database/sql.

All maintained versions of PostgreSQL are supported. Older versions may work, but this is not tested.

API docs: https://pkg.go.dev/github.com/lib/pq

Install with:

go get github.com/lib/pq@latest

Features

• SSL
• Handles bad connections for database/sql
• Scan time.Time correctly (i.e. timestamp[tz], time[tz], date)
• Scan binary blobs correctly (i.e. bytea)
• Package for hstore support
• COPY FROM support
• pq.ParseURL for converting urls to connection strings for sql.Open.
• Many libpq compatible environment variables
• Unix socket support
• Notifications: LISTEN/NOTIFY
• pgpass support
• GSS (Kerberos) auth

Running Tests

Tests need to be run against a PostgreSQL database; you can use Docker compose to start one:

docker compose up -d

This starts the latest PostgreSQL; use docker compose up -d pg«v» to start a different version.

In addition, your /etc/hosts currently needs an entry:

127.0.0.1 postgres postgres-invalid

Or you can use any other PostgreSQL instance; see testdata/init/docker-entrypoint-initdb.d for the required setup. You can use the standard PG* environment variables to control the connection details; it uses the following defaults:

PGHOST=localhost
PGDATABASE=pqgo
PGUSER=pqgo
PGSSLMODE=disable
PGCONNECT_TIMEOUT=20

PQTEST_BINARY_PARAMETERS can be used to add binary_parameters=yes to all connection strings:

PQTEST_BINARY_PARAMETERS=1 go test

Tests can be run against pgbouncer with:

docker compose up -d pgbouncer pg18
PGPORT=6432 go test ./...

and pgpool with:

docker compose up -d pgpool pg18
PGPORT=7432 go test ./...

You can use PQGO_DEBUG=1 to make the driver print the communication with PostgreSQL to stderr; this works anywhere (test or applications) and can be useful to debug protocol problems.

For example:

% PQGO_DEBUG=1 go test -run TestSimpleQuery
CLIENT → Startup                 69  "\x00\x03\x00\x00database\x00pqgo\x00user [..]"
SERVER ← (R) AuthRequest          4  "\x00\x00\x00\x00"
SERVER ← (S) ParamStatus         19  "in_hot_standby\x00off\x00"
[..]
SERVER ← (Z) ReadyForQuery        1  "I"
         START conn.query
         START conn.simpleQuery
CLIENT → (Q) Query                9  "select 1\x00"
SERVER ← (T) RowDescription      29  "\x00\x01?column?\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x17\x00\x04\xff\xff\xff\xff\x00\x00"
SERVER ← (D) DataRow              7  "\x00\x01\x00\x00\x00\x011"
         END conn.simpleQuery
         END conn.query
SERVER ← (C) CommandComplete      9  "SELECT 1\x00"
SERVER ← (Z) ReadyForQuery        1  "I"
CLIENT → (X) Terminate            0  ""
PASS
ok      github.com/lib/pq       0.010s