Is it possible that information_schema.columns doesn't hold an user table column information? I am facing a strange issue here. I have a table which is not visible in information_schema.columns view. What could be the reason for that.

Note: I am using RDS Aurora Postgresql 9.6.12
You will only see entries for a table in the information_schema views if you have permissions on the table in question.

You can get column metadata for tables where you have no access from pg_attribute, but you have to deal with PostgreSQL's internal data structures that may change between versions.