Export a Table or Query Result to a CSV File from Postgres

To export data from a table T (or any result of a query) in a PostgreSQL database use the following command:

$ psql -h localhost
       -U database_usr
       -d database_name
       -c "COPY (SELECT * FROM T) 
           TO '/path/file.csv' 
           DELIMITER ',' CSV HEADER;"

Notes:

• The query should be on one line; it is split here for readability.
• Make sure you have the correct permissions to write to the directory referenced. The command may need to be run with sudo.