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SQL for Inquiry-to-Reservation Conversion

MediumSQL · PostgreSQL00:00
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Your question is SQL for Inquiry-to-Reservation Conversion. Start with the requirements and the two tables on the right.

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Problem

Extra Space Storage operations leaders want a weekly view of how effectively store inquiries convert into reservations. Write a PostgreSQL query that combines daily inquiry and reservation metrics by store and date, then calculates the overall weekly reservation conversion rate.

Requirements

  1. Use store_inquiries_daily as the reporting base so weeks with inquiries remain visible even when no reservation record exists.
  2. Join reservations by both store_id and activity date, then group records by the Monday week start returned by DATE_TRUNC('week', ...).
  3. Return total inquiries, total reservations, and conversion rate as a percentage rounded to two decimal places. Treat missing reservation counts as zero and avoid division by zero.
  4. Sort the results chronologically by week.

Schema

store_inquiries_daily
ColumnTypeDescription
store_idPKINTIdentifier for the Extra Space Storage store
inquiry_datePKDATEDate inquiries were received
inquiry_countINTNumber of inquiries received that day
store_reservations_daily
ColumnTypeDescription
store_idPKINTIdentifier for the Extra Space Storage store
reservation_datePKDATEDate reservations were recorded
reservation_countINTNumber of reservations recorded that day
Tablesstore_inquiries_dailystore_reservations_daily
Your solutionPostgreSQL
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