THIS BLOCK IS THE SAME FOR ALL QUESTIONS
You must design a landscaper marketplace.
A person can register as a landscaper. She then chooses the services she offers from a pre-established list. She then declares - by selecting on a calendar - her availability (a start date and an end date, the days are always whole).
Another person can register on the site as a client. She can then select the service or services she is looking for. A list of landscapers is then presented to her with a filter that allows her to only present landscapers available for certain days / periods.
If the client finds an adequate landscaper, he can then select the dates he actually needs and then place an order.
All quiz questions refer to this problem.
####Two important constraints are added to answer the questions:
No data redundancy is tolerated.
We will consider the storage of structured data (table, hash, json, etc.) in a single data field impossible.
In order to perform a query listing the free availability of a landscaper, the availability table must contain a boolean to indicate if the availability has already been reserved.