Re: columns for count histograms of values
| От | chester c young |
|---|---|
| Тема | Re: columns for count histograms of values |
| Дата | |
| Msg-id | 357171.1486.qm@web54307.mail.re2.yahoo.com обсуждение исходный текст |
| Ответ на | columns for count histograms of values (Alexy Khrabrov <deliverable@gmail.com>) |
| Ответы |
Re: columns for count histograms of values
|
| Список | pgsql-sql |
--- Alexy Khrabrov <deliverable@gmail.com> wrote:
> Greetings -- I have a table of the kind
>
> Ratings:
> id integer
> rating smallint
>
> -- where value can take any value in the range 1 to 5. Now I want to
>
> have a statistical table Stats of the form
>
> id integer
> min smallint
> max smallint
> avg real
> r1 integer
> r2 integer
> r3 integer
> r4 integer
> r5 integer
>
> -- how can I create it in one pass over Ratings?
select id, min(rating), max(rating), avg(rating), sum( case rating = 1 then 1 else 0 end ), ...
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