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Creating a JSON Document IV

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Question of the Day

Creating a JSON Document IV

I have this data in a table called dbo.NFLTeams

TeamID  TeamName       City             YearEstablished
------  --------       ----             ---------------
1       Cowboys        Dallas           1960
2       Eagles         Philadelphia     1933
3       Packers        Green Bay        1919
4       Chiefs         Kansas City      1960
5       49ers          San Francisco    1946
6       Broncos        Denver           1960
7       Seahawks       Seattle          1976
8       Patriots       New England      1960
If I run this code, how many rows are returned?
SELECT 
  YearEstablished,
  json_objectagg(city : TeamName)
FROM dbo.NFLTeams
GROUP BY  YearEstablished;

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