sum query
От | Keith Worthington |
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Тема | sum query |
Дата | |
Msg-id | 20041203213340.M8095@narrowpathinc.com обсуждение исходный текст |
Ответы |
Re: [despammed] sum query
|
Список | pgsql-sql |
Hi All, I am trying to join three tables and sum the quantities. The first table contains all of the possible items. The second table contains orders and the third table contains the items on each order. For all items found in tbl_item I need the total quantity on open orders. If an item is not on any open order the quantity should be zero. Can someone please explain the best way to do this? tbl_item id | ... ------+... AB12 | ... CD34 | ... EF34 | ... GH12 | ... JK56 | ... tbl_order order | closed |... ------+--------+... 1 | false |... 2 | true |... 3 | true |... 4 | false |... 5 | false |... tbl_item order | id | quantity ------+-------+--------- 1 | AB12 | 10 1 | CD34 | 5 2 | CD34 | 3 3 | EF34 | 2 3 | GH12 | 20 4 | GH12 | 4 5 | AB12 | 5 id | quantity ------+--------- AB12 | 15 CD34 | 5 EF34 | 0 GH12 | 4 JK56 | 0 Kind Regards, Keith ______________________________________________ 99main Internet Services http://www.99main.com
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