SELECT score FROM t WHERE id in (2, 4) HAVING COUNT(*) = 2 /* replace this with the number of IDs */
This will select the rows with ID 2 and 4. TheHAVINGclause then ensures that we find both rows; if one of them is missing, the count will be less than 2.
This is an example of a "collection within a collection" query. I recommend using thehavingclause for aggregation as it is the most flexible method.
select score from t group by score having sum(id = 2) > 0 and -- has id = 2 sum(id = 4) > 0 -- has id = 4
What this does is aggregate by score. Then the first part of thehavingclause (sum(id = 2)) counts how many "2"s there are in each fraction. The second one is the number of "4". Only scores of "2" and "4" are returned.
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This will select the rows with ID 2 and 4. The
HAVINGclause then ensures that we find both rows; if one of them is missing, the count will be less than 2.This assumes
idis the only column.This is an example of a "collection within a collection" query. I recommend using the
havingclause for aggregation as it is the most flexible method.What this does is aggregate by score. Then the first part of the
havingclause (sum(id = 2)) counts how many "2"s there are in each fraction. The second one is the number of "4". Only scores of "2" and "4" are returned.