4. Deluxe Discovery Expeditions (DDE) specializes in curated journeys for groups exploring the
wonders of the New York City area. As DDE expands rapidly, managing diverse information
demands becomes challenging. The company's operations are outlined as follows:
* DDE offers various distinct excursions. Each excursion characterized by details such as the excursions title,
estimated duration (in hours), and corresponding fee. Guides are identified by a unique guide ID, and the
system should also store the guide's full name, home address, and date of recruitment. Guides undergo
qualification tests to lead specific excursions. It's vital to track which guides are qualified to lead which
excursions and the date of their qualification test completion for each excursion. A guide may be qualified
to lead multiple excursions, while an excursion can have numerous qualified guides. Newly recruited guides
may or may not be qualified to lead any excursions, just as a new excursion may or may not have any
qualified guides.
* Every excursion must be designed to explore at least three destinations. For each destination, details such
as name, category, and official description are maintained. Some destinations (e.g., Central Park) are visited
by multiple excursions, while others (e.g., Statue of Liberty) are exclusive to a single excursion. Each
destination is visited by at least one excursion. The sequence in which the excursion visits each destination
should also be recorded.
* When an excursion is conducted, it's termed as an "outing." DDE schedules outings well in advance for
promotional purposes and to inform employees of their forthcoming work schedules. An excursion can
have multiple scheduled outings, although newly designed excursion may not have any outings
scheduled. Each outing corresponds to a single excursion and is scheduled for a specific date and time.
All outings must be associated with an excursion. Since all excursions at DDE are guided, each outing
requires assignment of a guide. Each outing is assigned exactly one guide. Occasionally, guides are
tasked with leading an outing of an excursion even if they aren't officially qualified for that excursion.
Newly recruited guides may not have led any outings yet.
* Tourists, referred to as "clients" by DDE, pay to participate in scheduled outings. For each client, details
such as name and telephone number are recorded. Clients can register for multiple outings, and each
outing can accommodate multiple clients. Records are retained only for clients who have registered for at
least one outing, although newly scheduled outings may not have any registered clients yet.