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Find Restaurants With Zero Bookings
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Find Restaurants With Zero Bookings

MediumSQL · PostgreSQL

Problem

Given two tables, one with restaurant details and one with daily reservation logs, write a query to identify restaurants that have had zero bookings in the past week at OpenTable.

For this exercise, define the past week as February 10, 2025 through February 16, 2025, inclusive.

Output

  1. Return one row per restaurant with restaurant_id, restaurant_name, and bookings_last_7_days.
  2. Include restaurants with no reservation-log rows or only zero or NULL booking counts during the period, and exclude restaurants with positive bookings.
  3. Order by restaurant_id ascending.

Schema

restaurants
ColumnTypeDescription
restaurant_idPKINTUnique identifier for the restaurant
restaurant_nameVARCHAR(150)Display name of the restaurant
cityVARCHAR(100)Restaurant city
daily_reservation_logs
ColumnTypeDescription
log_idPKINTUnique identifier for the daily log row
restaurant_idINTRestaurant associated with the log
reservation_dateDATEDate represented by the log
booking_countINTNumber of bookings recorded for the restaurant on that date
Tablesrestaurantsdaily_reservation_logs
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