If your query took longer and never ending then possibility tables are under deadlock. You can easily identify the deadlock in postgres and kill the lock.
SELECT * FROM pg_locks pl LEFT JOIN pg_stat_activity psa ON pl.pid = psa.pid where state= 'active'
Find the records which are under deadlock
select
pid, state, usename, query, query_start
from
pg_stat_activity
where
pid in
(
select
pid
from
pg_locks pgl
join pg_class pgc on pgl.relation = pgc.oid
where
pgc.relkind = 'r'
and pgc.relname = 'your_table'
);
Observe the query output and identify your queries causing deadlock.
Then Kill the ProcessID's one by one
SELECT pg_cancel_backend(0001);
if Deadlock still there, your PID still visible in pg_locks table then use below query
select pg_terminate_backend(0001)
