SESSION NAME: Advance Select - 1
QUESTION NAME: Weather Observation - Query 3
TABLE DESCRIPTION:
Let N be the number of CITY entries in STATION, and let
N' be the number of distinct CITY names in STATION;
query the value of N - N' from STATION. In other words,
find the difference between the total number of CITY
entries in the table and the number of distinct CITY
entries in the table.
CODE:
select COUNT(CITY)-COUNT(DISTINCT CITY) from STATION;
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