Postgres maintainance queries

postgres.sql

-- Finding open connections
SELECT * FROM pg_stat_activity;
-- Dropping open connections
SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = <databasename> AND pid <> pg_backend_pid()  AND state in (  'idle');
-- Describing a table
select column_name, data_type, character_maximum_length from INFORMATION_SCHEMA.COLUMNS where table_name = 'pg_stat_activity';