Porovnani poctu pres COUNT s polickem – MySQL – Fórum – Programujte.com

Mam neco takoveho. Potreboval bych to napsat nejak elegantne do jednoho radku a treti sloupec by byl porovnani obou hodnot. Jedna se o pocet mailu, limit mailu a zda uzivatel tento limit prekrocil.

(SELECT COUNT(*) AS `count`,NULL FROM `contact`)
UNION ALL
(SELECT NULL,`pay_mail_limit` AS `limit` FROM `user_acount` WHERE '.$u.' LIMIT 1)

count = COUNT * tabulky "contact"
limit = policko v tabulce "acount"
A vysledkem bych chtel mit tabulku
count, limit, count<limit (true/false nebo rozdil)
Abych pak nemusel v php davat slozitou podminku s issety, jestli existuji obe hodnoty, nejsou null a pod.

V tabulce contact neni zadna informace o uzivateli?

Smysl by mi to davalo treba takto:

SELECT
	  c.user_id
	, c.pocet
	, a.pay_mail_limit AS limit
	, a.pay_mail_limit - c.pocet AS rozdil
FROM
	(
		SELECT
			  user_id
			, COUNT(*) AS pocet
		FROM
			contact
		GROUP BY
			user_id
	) AS c
	INNER JOIN user_account AS a ON a.user_id = c.user_id

Nj, po obede vypinam, takove lehke :) Jo, $u je "`id_user`='1'" a mel jsem tam par preklepu v dotazu.

SELECT
  c.`count`,
  b.`pay_mail_limit` AS `limit`,
  c.`count`<b.`pay_mail_limit` AS `diff`
FROM
  (SELECT COUNT(*) AS `count`,a.`id_user` FROM `contact` a WHERE a.".$u.") c
  LEFT JOIN `user_acount` b ON b.`id_user`=c.`id_user`
LIMIT 1