Hello, > I went this way, but for a large number of user_id's, it's quite slow: > > CREATE VIEW v_views AS > SELECT user_id, product_id, count(*) as views > FROM viewlog > GROUP BY user_id, product_id > > SELECT > DISTINCT user_id, > (SELECT product_id FROM v_views inn WHERE inn.user_id = out.user_id > ORDER BY views DESC LIMIT 1) as product_id, > (SELECT views FROM v_views inn WHERE inn.user_id = out.user_id ORDER BY > views DESC LIMIT 1) as views > FROM > v_views out > Does this work faster? select x.user_id,y.product_id,x.count from (select user_id, max(count ) as count from (select user_id,product_id, count(*) as count from viewlog group by user_id,product_id) as x group by user_id ) as x inner join (select user_id,product_id, count(*) as count1 from viewlog group by user_id,product_id ) as y on x.user_id=y.user_id and x.count=y.count1
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