Treba ti nesto poput
Code:
SELECT (SELECT COUNT(value)
FROM exponate
WHERE value >= 30
AND value <= 50)
/
(SELECT COUNT(value)
FROM exponate)
*
100
FROM neka_tabela_sa_samo_jednim_redom
Za Oracle neka_tabela_sa_samo_jednim_redom = DUAL
Za PostgreSQL moze da se izosatavi kompletna FROM klauzula
Sledeci kod je uopsten, koristi privremenu tabelu i radi na vecini sistema:
Code:
SELECT SUM(t.b) / SUM(t.i) * 100
FROM (SELECT COUNT(value) AS b, 0 AS i
FROM exponate
WHERE value >= 30
AND value <= 50
UNION ALL
SELECT 0 AS b, COUNT(value) AS i
FROM exponate
) AS t
"The best code is no code at all."
- Zidar (ES član)
"Biggest obstacle to learning
SQL is unlearning procedural
programming." - Joe
Celko
"Minimize code, maximize data."
- A. Neil Pappalardo