Описание тега psql
Primary interactive shell for PostgreSQL.
NOT a synonym for PostgreSQL.
psql is a terminal-based client to PostgreSQL, that's packaged with the software. It lets you edit queries interactively, issue them to PostgreSQL, and see the results. You can read and write to / from files and use it for scripting.
Additionally, psql provides a set of meta-commands and other shell-like features to facilitate writing scripts and automating a wide range of tasks.
Questions with this tag should probably be tagged postgresql, too.
But only questions dealing with the command-line interface should be tagged psql.
Questions referring to the procedural language "psql" for the Firebird database should be tagged with firebird-psql