I have created the following index on standard beer-sample:
country) USING GSI;
The following query uses this index according to the explain plan and in fact the index is a covering index for this query :
SELECT count (country) from
The following query does not use this index according to the explain plan
SELECT country, count (*) from
beer-sample group by country;
Why does this second query not use the index when the same index should still be seen as a covering index?