How to recover password in PostgreSQL ?

1. If password is not provided for the super user while installing postgresql, it can be changed by following steps:

• Open pg_hba.conf, change authentication method to trust.
• Restart Database Server
• Login into psql. (# psql -d <database name> -U <super user>
• Inside psql prompt,
  Alter role <rolename> with password 'yourpassword';
  
  
• Then quit. Now change trust authentication to md5 in pg_hba.conf.
• Restart Database Server
• Now, while log in to psql, you need to supply password while prompting.

2. By default, authentication method of postgres is by ident_user type. Change it to md5 or trust in pg_hba.conf file. Md5 is recommended.