1-- 2-- SELECT_DISTINCT 3-- 4 5-- 6-- awk '{print $3;}' onek.data | sort -n | uniq 7-- 8SELECT DISTINCT two FROM tmp ORDER BY 1; 9 10-- 11-- awk '{print $5;}' onek.data | sort -n | uniq 12-- 13SELECT DISTINCT ten FROM tmp ORDER BY 1; 14 15-- 16-- awk '{print $16;}' onek.data | sort -d | uniq 17-- 18SELECT DISTINCT string4 FROM tmp ORDER BY 1; 19 20-- 21-- awk '{print $3,$16,$5;}' onek.data | sort -d | uniq | 22-- sort +0n -1 +1d -2 +2n -3 23-- 24SELECT DISTINCT two, string4, ten 25 FROM tmp 26 ORDER BY two using <, string4 using <, ten using <; 27 28-- 29-- awk '{print $2;}' person.data | 30-- awk '{if(NF!=1){print $2;}else{print;}}' - emp.data | 31-- awk '{if(NF!=1){print $2;}else{print;}}' - student.data | 32-- awk 'BEGIN{FS=" ";}{if(NF!=1){print $5;}else{print;}}' - stud_emp.data | 33-- sort -n -r | uniq 34-- 35SELECT DISTINCT p.age FROM person* p ORDER BY age using >; 36 37-- 38-- Check mentioning same column more than once 39-- 40 41EXPLAIN (VERBOSE, COSTS OFF) 42SELECT count(*) FROM 43 (SELECT DISTINCT two, four, two FROM tenk1) ss; 44 45SELECT count(*) FROM 46 (SELECT DISTINCT two, four, two FROM tenk1) ss; 47 48-- 49-- Also, some tests of IS DISTINCT FROM, which doesn't quite deserve its 50-- very own regression file. 51-- 52 53CREATE TEMP TABLE disttable (f1 integer); 54INSERT INTO DISTTABLE VALUES(1); 55INSERT INTO DISTTABLE VALUES(2); 56INSERT INTO DISTTABLE VALUES(3); 57INSERT INTO DISTTABLE VALUES(NULL); 58 59-- basic cases 60SELECT f1, f1 IS DISTINCT FROM 2 as "not 2" FROM disttable; 61SELECT f1, f1 IS DISTINCT FROM NULL as "not null" FROM disttable; 62SELECT f1, f1 IS DISTINCT FROM f1 as "false" FROM disttable; 63SELECT f1, f1 IS DISTINCT FROM f1+1 as "not null" FROM disttable; 64 65-- check that optimizer constant-folds it properly 66SELECT 1 IS DISTINCT FROM 2 as "yes"; 67SELECT 2 IS DISTINCT FROM 2 as "no"; 68SELECT 2 IS DISTINCT FROM null as "yes"; 69SELECT null IS DISTINCT FROM null as "no"; 70 71-- negated form 72SELECT 1 IS NOT DISTINCT FROM 2 as "no"; 73SELECT 2 IS NOT DISTINCT FROM 2 as "yes"; 74SELECT 2 IS NOT DISTINCT FROM null as "no"; 75SELECT null IS NOT DISTINCT FROM null as "yes"; 76