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Prepare > SQL > Basic Select > Weather Observation Station 4

stem_sw 2023. 7. 8. 22:11
 

Weather Observation Station 4 | HackerRank

Find the number of duplicate CITY names in STATION.

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문제


Find the difference between the total number of CITY entries in the table and the number of distinct CITY entries in the table.

 

 

 

 

코드


SELECT COUNT(CITY) - COUNT(DISTINCT(CITY)) FROM STATION;