To check if a password is correct in Postgres, you would follow these steps:
1. Connect to the Postgres database using a Postgres client such as psql or pgAdmin.
2. Identify the user whose password you want to check.
3. Use the following command to verify the user's password:
`SELECT pg_authid.rolname, pg_authid.rolpassword FROM pg_roles WHERE rolname='';`
Replace `` with the user whose password you want to check.
4. If the password is correct, you will see a hash value in the `rolpassword` column. If the password is incorrect, this column will be empty.
Note that Postgres stores password hashes, not plaintext passwords, so you can't directly compare the password you have with the one stored in the database. Instead, you need to hash the password you have using the same algorithm that Postgres uses (usually MD5 or SHA-256), and compare the resulting hash with the one stored in the `rolpassword` column.