MySQL 8.0

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select version();


version()


8.0.17


CREATE TABLE zip_unique
(     store_nbr integer
     ,zipcode varchar(30)
     ,distance float);
INSERT INTO zip_unique (store_nbr, zipcode, distance)
VALUES (123, '76135', 2.356)
     , (456, '76135', 3.002)
     , (789, '76135', 9.521);
SELECT * FROM zip_unique;


store_nbr
zipcode
distance


123
76135
2.356

456
76135
3.002

789
76135
9.521


SELECT store_nbr
      ,zipcode
      ,distance
      ,ROW_NUMBER() OVER(PARTITION BY ZIPCODE
                             ORDER BY DISTANCE) AS ROW_RANK
  FROM zip_unique;


store_nbr
zipcode
distance
ROW_RANK


123
76135
2.356
1

456
76135
3.002
2

789
76135
9.521
3