Dump the query results to .csv

How do you print the result of a PostgreSQL query in CSV or TSV format from the command line?

psql -d <database_name> -c "<command>" -A -F , -X -o <file_name.csv>

Copy (select * from users) To '/tmp/sample_data.csv' With CSV DELIMITER ',' HEADER;

Terminate active connections to the database

PostgreSQL DROP DATABASE

SELECT pg_terminate_backend (pg_stat_activity.pid) 
FROM pg_stat_activity 
WHERE pg_stat_activity.datname = 'process_designer';

Generate a SQL with specified columns not present

SELECT 'SELECT ' || string_agg('o' || '.' || c.column_name, ', ') || ' FROM ' || table_name || ' o' As sqlstmt
FROM information_schema.columns As c
WHERE table_name = 'office' AND
      c.column_name NOT IN ('id', 'deleted')
GROUP BY c.table_name;

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Create a copy of psql database.

CREATE DATABASE <new_database_name> template <old_database_name>

Updating size of varchar in Postgres column

alter table <table_name> alter COLUMN <column_name> type varchar(<new_size>);

Get data greater than days

select * from users where created_at < (CURRENT_DATE - INTERVAL '30 days');