How to change PG column to NULLABLE TRUE?

Question

How can I do this using Postgres? I tried the code below, but it does not work:

ALTER TABLE mytable ALTER COLUMN mycolumn BIGINT NULL; 

Answer 1

From the exact guide :

 ALTER TABLE mytable ALTER COLUMN mycolumn DROP NOT NULL; 

There is no need to specify a type when you just change the nullability value.

Answer 2

For Oracle users:

 alter table mytable modify(mycolumn null);