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Donor-to-Acceptor Ratio Query
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Donor-to-Acceptor Ratio Query

MediumSQL · PostgreSQL

Problem

Given two tables, DONOR and ACCEPTOR, find the city with the best and worst donor-to-acceptor ratio.

Calculate the ratio as donor count divided by acceptor count. Consider only cities with at least one donor and one acceptor. Break ratio ties alphabetically by city.

Output

  1. Return one row for each result, with columns ratio_type, city, donor_count, acceptor_count, and donor_to_acceptor_ratio.
  2. Include exactly one best row and one worst row.
  3. Order best before worst.

Schema

donor
ColumnTypeDescription
donor_idPKINTUnique donor identifier
cityVARCHAR(100)Donor city
acceptor
ColumnTypeDescription
acceptor_idPKINTUnique acceptor identifier
cityVARCHAR(100)Acceptor city
Tablesdonoracceptor
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