ydb/yql/essentials/tests/postgresql/cases/limit.sql

--
-- LIMIT
-- Check the LIMIT/OFFSET feature of SELECT
--
SELECT ''::text AS two, unique1, unique2, stringu1
		FROM onek WHERE unique1 > 50
		ORDER BY unique1 LIMIT 2;
SELECT ''::text AS five, unique1, unique2, stringu1
		FROM onek WHERE unique1 > 60
		ORDER BY unique1 LIMIT 5;
SELECT ''::text AS two, unique1, unique2, stringu1
		FROM onek WHERE unique1 > 60 AND unique1 < 63
		ORDER BY unique1 LIMIT 5;
SELECT ''::text AS three, unique1, unique2, stringu1
		FROM onek WHERE unique1 > 100
		ORDER BY unique1 LIMIT 3 OFFSET 20;
SELECT ''::text AS zero, unique1, unique2, stringu1
		FROM onek WHERE unique1 < 50
		ORDER BY unique1 DESC LIMIT 8 OFFSET 99;
SELECT ''::text AS eleven, unique1, unique2, stringu1
		FROM onek WHERE unique1 < 50
		ORDER BY unique1 DESC LIMIT 20 OFFSET 39;
SELECT ''::text AS ten, unique1, unique2, stringu1
		FROM onek
		ORDER BY unique1 OFFSET 990;
SELECT ''::text AS five, unique1, unique2, stringu1
		FROM onek
		ORDER BY unique1 OFFSET 990 LIMIT 5;
SELECT ''::text AS five, unique1, unique2, stringu1
		FROM onek
		ORDER BY unique1 LIMIT 5 OFFSET 900;
-- Test null limit and offset.  The planner would discard a simple null
-- constant, so to ensure executor is exercised, do this:
select * from int8_tbl limit (case when random() < 0.5 then null::bigint end);
select * from int8_tbl offset (case when random() < 0.5 then null::bigint end);
-- Test assorted cases involving backwards fetch from a LIMIT plan node
begin;
rollback;
select sum(tenthous) as s1, sum(tenthous) + random()*0 as s2
  from tenk1 group by thousand order by thousand limit 3;
SELECT  thousand
		FROM onek WHERE thousand < 5
		ORDER BY thousand FETCH FIRST 2 ROW ONLY;
-- SKIP LOCKED and WITH TIES are incompatible
SELECT  thousand
		FROM onek WHERE thousand < 5
		ORDER BY thousand FETCH FIRST 1 ROW WITH TIES FOR UPDATE SKIP LOCKED;
-- should fail
SELECT ''::text AS two, unique1, unique2, stringu1
		FROM onek WHERE unique1 > 50
		FETCH FIRST 2 ROW WITH TIES;
-- leave these views