--
-- MULTI_LIMIT_CLAUSE
--


-- Display debug messages on limit clause push down.

SET client_min_messages TO DEBUG1;

-- Check that we can correctly handle the Limit clause in distributed queries.
-- Note that we don't have the limit optimization enabled for these queries, and
-- will end up fetching all rows to the master database.

SELECT count(*) count_quantity, l_quantity FROM lineitem WHERE l_quantity < 32.0
	GROUP BY l_quantity
	ORDER BY count_quantity ASC, l_quantity ASC;

SELECT count(*) count_quantity, l_quantity FROM lineitem WHERE l_quantity < 32.0
	GROUP BY l_quantity
	ORDER BY count_quantity DESC, l_quantity DESC;

SELECT count(*) count_quantity, l_quantity FROM lineitem WHERE l_quantity < 32.0
	GROUP BY l_quantity
	ORDER BY count_quantity ASC, l_quantity ASC LIMIT 5;

SELECT count(*) count_quantity, l_quantity FROM lineitem WHERE l_quantity < 32.0
	GROUP BY l_quantity
	ORDER BY count_quantity ASC, l_quantity ASC LIMIT 10;

SELECT count(*) count_quantity, l_quantity FROM lineitem WHERE l_quantity < 32.0
	GROUP BY l_quantity
	ORDER BY count_quantity DESC, l_quantity DESC LIMIT 10;

-- Check that we can handle limits for simple sort clauses. We order by columns
-- in the first two tests, and then by a simple expression in the last test.

SELECT min(l_orderkey) FROM  lineitem;
SELECT l_orderkey FROM lineitem ORDER BY l_orderkey ASC LIMIT 1;

SELECT max(l_orderkey) FROM lineitem;
SELECT l_orderkey FROM lineitem ORDER BY l_orderkey DESC LIMIT 1;
SELECT * FROM lineitem ORDER BY l_orderkey DESC, l_linenumber DESC LIMIT 3;

SELECT max(extract(epoch from l_shipdate)) FROM lineitem;
SELECT * FROM lineitem
	ORDER BY extract(epoch from l_shipdate) DESC, l_orderkey DESC LIMIT 3;

-- Exercise the scenario where order by clauses don't have any aggregates, and
-- that we can push down the limit as a result. Check that when this happens, we
-- also sort on all group by clauses behind the covers.

SELECT l_quantity, l_discount, avg(l_partkey) FROM lineitem
	GROUP BY l_quantity, l_discount
	ORDER BY l_quantity LIMIT 1;

-- Results from the previous query should match this query's results.

SELECT l_quantity, l_discount, avg(l_partkey) FROM lineitem
	GROUP BY l_quantity, l_discount
	ORDER BY l_quantity, l_discount LIMIT 1;

SET client_min_messages TO NOTICE;