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Wednesday 21 January 2026

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SQL Data Design

SQL Data Design #3/9

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.

Author: W3D TeamStatus: PublishedQuestion passed 720 times
-1
Reviews from developers
developer avatar
Auteur anonyme
15/12/2024
Ma réflexion : Si tu as une table avec les disponibilités du paysagiste, alors ce sera redondant d'avoir une table "disponibilité" avec deux colonnes (user et disponibilité). Alors que, tu peux tout simplment faire une requête sur les dates de dispo et si ça te retourne rien (tableau vide ou false), alors c'est que le paysagiste n'est pas dispo.
developer avatar
Auteur anonyme
16/12/2024
Tu peux contribuer en ajoutant une explication de la réponse.

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