1-- 2-- SELECT_DISTINCT_ON 3-- 4 5SELECT DISTINCT ON (string4) string4, two, ten 6 FROM tmp 7 ORDER BY string4 using <, two using >, ten using <; 8 9-- this will fail due to conflict of ordering requirements 10SELECT DISTINCT ON (string4, ten) string4, two, ten 11 FROM tmp 12 ORDER BY string4 using <, two using <, ten using <; 13 14SELECT DISTINCT ON (string4, ten) string4, ten, two 15 FROM tmp 16 ORDER BY string4 using <, ten using >, two using <; 17 18-- bug #5049: early 8.4.x chokes on volatile DISTINCT ON clauses 19select distinct on (1) floor(random()) as r, f1 from int4_tbl order by 1,2; 20