sql - select top 10 with the highest average score -

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lets say, have product , score tables. 

product ------- id name  score ----- id productid scorevalue

i want top 10 products highest average scores, how average , select top 10 products in 1 select statement?

here mine selects unexpected rows

select top 10 product.productname score.score  product, score  product.id  in (select top 100  productid                          score                         group productid                         order sum(score) desc)  order score.score desc

give try,

with records (     select  a.id, a.name, avg(b.scorevalue) avg_score,             dense_rank() on (order avg(b.scorevalue) desc) rn        product             inner join score b                 on a.id = b.productid     group   a.id, a.name ) select  id, name, avg_score    records   rn <= 10 order   avg_score desc

the reason why not using top because not handle duplicate record having highest average. can use top ties instead.


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