Re: Search for lists
От | David Johnston |
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Тема | Re: Search for lists |
Дата | |
Msg-id | 2CE9F932-85E0-44BC-82D2-A01F98DDB575@yahoo.com обсуждение исходный текст |
Ответ на | Search for lists (Daron Ryan <daron.ryan@gmail.com>) |
Ответы |
Re: Search for lists
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Список | pgsql-general |
An alternative approach would be to select using a IN condition on the where clause and group by column 1 and column 2. Then, using this as a sub-select group by the resultant column 1 and a count on column two. The matching identifiers arethose with a count equal to the number of entries in the original IN condition. Basically count how many of values each distinct key in column 1 matches and keep those keys where the count and the numberof values match. David J. On Jun 18, 2011, at 17:51, Daron Ryan <daron.ryan@gmail.com> wrote: > Hello, > > I need to search a table to find sets of rows that have a column matching itself for the whole set and another column matchingrow for row with a list I am going to supply. The result I should receive should be value of the column that matchesitself. > > For example given the following data in my table: > > 3; 1 > 3; 2 > 4; 8 > 4; 9 > 4; 10 > > I might need to search for 1,2. This should produce the result 3. Or if I were to search for 8, 9, 10 the result shouldbe 4. Searching for 8, 9 should produce an empty result as should 8, 9, 10, 11. > > Can anyone recommend a strategy? > > -- > Sent via pgsql-general mailing list (pgsql-general@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general
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