Problem in retrieving and update users records

Hi,

Can we do the following task with users table?

  • Change password for logged in users?
  • Retrieve Password with identity(email address)?
  • We have added the relation column in users table, which contain the Object IDs of another table with one to many relation. So, can we add the object id of related table in this column(users table) ?

Thanks!

Regards,
Mark