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While the projection specification that we set for ourselves is fulfilled, there is more that can be done on this program to make it more serviceable in a production environment. Some areas that you might look at for further practice are:
- Set the host, database, username, and password from command-line options. You will naturally need to error-check each of them. You will probably want to use the
getpassmodule to accept the password in production environments. - Set an option for the column variable and testing whether that column exists in the chosen database.
- Set up error-checking for the results itself.
The world database has a few other tables besides City. Can you aggregate their records in Python without using a JOIN statement?