sudo -u postgres psql -d postgres -c 'SELECT version();'

Category: Databases & SQL

sudo -u postgres psql -d postgres -c 'SELECT version();'

Query as the postgres superuser

sudo -u postgres switches to the OS user that owns the cluster, so peer authentication admits you as the postgres superuser without a password. -d postgres targets the maintenance database and -c runs a single statement. The standard entry point before application roles exist.
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