Laurenz Albe <laurenz.albe@cybertec.at> writes:
> On Tue, 2020-01-07 at 14:58 +0530, Shrikant Bhende wrote:
>> I am trying to add a column to a table but it's not working, I have also tried
>> reindex and drop on the same table but those commands are also getting stuck.
> There is a concurrent session which has an open transaction which
> holds some lock on the table in question.
Yes, that looks like the cause. The pg_locks view could help you
find the culprit session.
regards, tom lane