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
Regards,
Jayadevan
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