Table with too many nullable columns - is there a better design? I have a user table with around 30 columns. Most of these columns are almost always null unless user decides to share additional info about themselves. For example, weight, height, religion, is_smoking, is_drinking, star_sign, school, job, etc. 

In my app, I have on option to filter users based on these values. I might be adding one or two columns like these in future. 

I was just wondering if there is a better design approach for situations like these. For some reason, it doesn't feel right to have all these nullable columns in the same table with login credentials. 

PS: I am using PostgreSQL 11.4 as the database management system.
You could have a table

CREATE TABLE user_info (
   id bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
   user_id bigint NOT NULL REFERENCES users,
   property text NOT NULL,
   value TEXT NOT NULL
);


and store the additional properties there. That would be the relational way of doing it.

In recent PostgreSQL versions you could also add a jsonb column for all such information.

With a GIN index on it you can filter efficiently as long as you are looking for certain keys and their value. But you won't be able to do advanced things like substring or similarity matches that way.

It is a matter of taste which one you prefer.