Re: Getting top 2 by Category
От | msi77 |
---|---|
Тема | Re: Getting top 2 by Category |
Дата | |
Msg-id | 143611294776056@web61.yandex.ru обсуждение исходный текст |
Ответ на | Getting top 2 by Category ("Ozer, Pam" <pozer@automotive.com>) |
Список | pgsql-sql |
There some ways to do this in one query. Look here: http://www.sql-ex.ru/help/select16.php --------------- 11.01.11, 22:00, "Ozer, Pam" <pozer@automotive.com>:> This is probably very simple but I am drawing a blank. Do I need tocreate a cursor to iterate through a table to grab the top 2 magazines per category? Here is my table and some data . The results I need are at the bottom. Any help would be greatly appreciated: CREATE TABLE magazinecategory( magazinecategoryidsmallint NOT NULL , magazineid smallint, categoryid smallint); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (1, 2, 3); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (2, 8, 3); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (3 9, 3); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (4, 10, 4); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (5, 11, 4); INSERT INTO magazinecategory( magazinecategoryid, magazineid, categoryid) VALUES (6, 12,4); The results I want areCategoryID MagazineID3 23 84 104 11 Pam Ozer>
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