रिपोर्ट_आईडी . द्वारा शीर्ष 'एन' रिकॉर्ड प्राप्त करें

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SELECT *
FROM (SELECT *,
         ROW_NUMBER() OVER(PARTITION BY report_id ORDER BY (SELECT 0)) AS RN
         FROM top_keywords
         WHERE ym BETWEEN '2010-05' AND '2010-05') TK
WHERE RN <= 10