Please read through this page entirely and carefully, before beginning your work.
Consider a MySQL-based database that stores information about employees in an organisation and their reporting chain. Write code (in a general-purpose language) that connects to this database, gathers this information into a suitable tree-like internal data structure, and then writes some portion of (or all of) this information onto standard output, using indentation and layout to represent the reporting chain.
Specifically, your program should take one or two command line arguments, the first of which gives the name of a database to connect to. It should then connect to this database on "sunapee", and gather information from the relation employee (name, role, manager). Then, it should print several lines to standard output, where each line gives the name of an employee, their role, and the total number of subordinates (direct or indirect) under them, in the format "%s: %s: %d subordinates" (in printf notation). If this employee has no subordinates, then the third field should be omitted. The subordinates of an employee should appear beneath that employee's name, indented using two leading spaces. This rule should be applied recursively: thus, second-level subordinates should appear below their respective immediate managers and should be indented using four leading spaces, etc. Further, all employees that are immediately under a particular manager should be listed in ascending alphabetical order of their names. Finally, the output should begin with the employee whose name is given as the second command line argument; if this argument is missing, then the output should begin with the top-level employee, indicated by a NULL value in the manager field. In the latter case, if there is more than one top-level employee, then you should print all of them (together with their subordinates, as described above) in ascending alphabetical order of their names.
There is a detailed example in the file ~cs33/data/hw3_empdata.txt, which I urge you to read and understand, very carefully. You must follow the above explicit output formatting instructions as well as the implicit ones in that example.
Consider, yet again, the actors and films example from Homeworks 1 and 2. Assume that the data from the relevant files in ~cs33/data/ have been loaded into the following tables in the MySQL database "filmdb" on "sunapee":
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actor (actor_ID, first_name, last_name) film (film_ID, film_name, description, year) actor_film (actor_ID, film_ID) |
Write code (in a general-purpose language) to perform the necessary updates on "filmdb". Specifically, your program should read four command line arguments that specify, in order, the first and last names of actor1 and the first and last names of actor2. It should then connect to "filmdb", check if the aforementioned common film condition applies and then behave as follows. If the condition applies, it should print (on standard output) a complete list of film names in which both of the given actors appear, in increasing order of film ID. Else (the condition does not apply), it should print nothing and effectively rename actor1 to actor2 in the database, updating the tables actor and actor_film as necessary. If any errors occur (e.g., inability to connect to the database, or update it, or a non-existent actor name), then you should print an appropriate informative error message to standard output and not make any changes to the database.