PostgreSQL

When it hangs, run the following

SELECT
    pg_terminate_backend(pid)
FROM
    pg_stat_activity
WHERE
    -- don't kill my own connection!
    pid <> pg_backend_pid()
    -- don't kill the connections to other databases
    AND datname = 'database_name'
    ;

Export all rows in a table to a CSV file: \copy stat_statlog to 'stat_statlog.csv' csv header