Question

I have 2 tables, book and temp_table.
There are 2 columns in book : book_id and tag_id, and only 1 column in temp_table (tag_id).

I need do selection used following rule:

• If book has ALL the tags from temp_table, it will be in result.

For example, there are 3 books.

   First one has tag_id: 1,2,3,4.
   Second - 1,3,4
   Third - 1,2,3,5

And temp_table contains tag_id:1,3,4.

Needed selection has to contains 1st and 2nd books. 3d book must not be in result set because it has tag_id = 5, which there isnt in temp_table.

Answer 1

select book_id
from book b
inner join temp_table t on t.tag_id = tag_id
group by book_id
having count(distinct tag_id) = (select count(distinct tag_id) from temp_table)