Re: Search for lists

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 are those 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 number of values match.

David J.

On Jun 18, 2011, at 17:51, Daron Ryan <daron(dot)ryan(at)gmail(dot)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 matching row for row with a list I am going to supply. The result I should receive should be value of the column that matches itself.
>
> 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 should be 4. Searching for 8, 9 should produce an empty result as should 8, 9, 10, 11.
>
> Can anyone recommend a strategy?
>
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