Need help for constructing query

Поиск
Список
Период
Сортировка
От Marco
Тема Need help for constructing query
Дата
Msg-id 4d8c97dc$0$7651$9b4e6d93@newsspool1.arcor-online.net
обсуждение исходный текст
Ответы Re: Need help for constructing query  (Radosław Smogura <rsmogura@softperience.eu>)
Список pgsql-general
Hi,

I have a table like this:

id    date        min    max    value
1    2011-03-25    20    30    17
3    2011-03-21    40    55    43
3    2011-03-23    40    55    52
2    2011-02-25    5        2
4    2011-03-15            74
4    2011-03-25            128
1    2011-03-22    20    30    24

I'm looking for a query that outputs the last rows (highest date) per id where
the value is between min and max. I already have problems displaying the last
rows per id. Something like

select id, max(date) from mytable group by id;

gives just the id and the date, not the other values. I think of doing this in
two steps:

1) Display the rows with the highest date per id. That gives as many rows as
   ids exist.
2) Remove the rows that do not match ( value<max and value>min )


Marco


В списке pgsql-general по дате отправления:

Предыдущее
От: Marco
Дата:
Сообщение: Re: Need help for constructing query
Следующее
От: "David Johnston"
Дата:
Сообщение: Re: Need help for constructing query