Final answer:
The error message 'psql: FATAL: database root does not exist' indicates that the PostgreSQL database named 'root' does not exist. To solve this error, you can either create a database with the name 'root' or provide the correct name of an existing database.
Step-by-step explanation:
The error message 'psql: FATAL: database root does not exist' indicates that the PostgreSQL database named 'root' does not exist. This error can occur if you are trying to connect to a database that has not been created or does not have the correct name. To solve this error, you can either create a database with the name 'root' or provide the correct name of the existing database you want to connect to.
For example, if you want to connect to an existing database named 'mydatabase', you can use the following command: psql -d mydatabase. Alternatively, you can create a new database with the name 'root' using the following command: createdb root.