enabling nestedloop and disabling hashjon

I want to disable the hashjoin algorithm used by postgres by default, and enable the nested loop join algorithm, can some one tell me how to do that.

I tried modifying the postgresql.conf file where I set the value enable_hashjoin=off and also enable_mergejoin=off, so that I could force postgres to use nested loop.

but postgres is still using the hash join algorithm even after modifying the postgresql code.

can some one tell me what I am doing wrong, or is there any other file where I need to modify to enable nested loop join algorithm.

Thanks