Filtering Based on Grouped Row Count
Question:
Can results be grouped and subsequently filtered based on the number of rows in each group?
Example Query:
SELECT * FROM mytable WHERE COUNT(*) > 1 GROUP BY name
Answer:
To achieve the desired filtering, the HAVING clause should be employed instead:
SELECT name, COUNT(*) FROM mytable GROUP BY name HAVING COUNT(*) > 1
By using HAVING, you can specify conditions that apply to the grouped results, in this case filtering for groups with more than one row.
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