PGUSER

PGUSER is an environment variable used by PostgreSQL client applications to specify the database user name to connect as. It is read by libpq-based tools and libraries when establishing a connection, providing a default username if none is supplied in the connection string or URL. If a user is explicitly provided in the connection string, that value takes precedence over PGUSER.

Setting PGUSER is common in shell environments. In Unix-like terminals, you can set it with export PGUSER="dbadmin". In Windows command prompts, you can set it with set PGUSER=dbadmin. The variable applies to subsequent client commands in the current session. Note that PGUSER does not supply a password; password handling is typically done via PGPASSWORD or a .pgpass file.

Usage considerations include the fact that PGUSER is primarily honored by libpq-based clients (such as psql, pg_dump, and applications using the libpq library). Other database drivers or clients may have different mechanisms for specifying the user, so PGUSER may not affect non-libpq tools.

Security considerations are important: environment variables can be read by other processes on the same host, so PGUSER should not be used to convey secret information. Use PGPASSWORD or a secure credential store (like .pgpass) for passwords, and prefer restricted access to the environment in shared systems.

See also: PGPASSWORD, PGHOST, PGPORT, PGDATABASE, and related PostgreSQL client environment variables.