In table A我有田地CENA
(价格),cena_za_kus
(每件价格),mnozstvi
(数量)。
In table B我有田地DPH
(vat).
我想添加一个更新/插入之前触发器,它将计算PRICE
字段,像这样:
price = (price_per_piece * count) + (price_per_piece * count * tableB.vat)
这可能吗?
谢谢。
编辑:以及行tableA 有一个foreign_keydph_id
指向相应的行table B.
CREATE TABLE `polozky` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`objednavka_id` int(11) NOT NULL,
`dph_id` int(11) NOT NULL,
`polozka` varchar(64) COLLATE utf8_unicode_ci NOT NULL,
`cena` float NOT NULL,
`mnozstvi` int(11) NOT NULL,
`cena_za_kus` float NOT NULL,
PRIMARY KEY (`id`),
KEY `IdObjednavka` (`objednavka_id`,`dph_id`),
KEY `objednavka_id` (`objednavka_id`),
KEY `dph_id` (`dph_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=63663 ;
ALTER TABLE `polozky`
ADD CONSTRAINT `polozky_ibfk_7` FOREIGN KEY (`objednavka_id`) REFERENCES `objednavky` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
ADD CONSTRAINT `polozky_ibfk_8` FOREIGN KEY (`dph_id`) REFERENCES `dph` (`id`) ON DELETE CASCADE ON UPDATE CASCADE;
and
CREATE TABLE `dph` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`sekce` varchar(64) COLLATE utf8_unicode_ci NOT NULL DEFAULT 'nastaveni',
`popis` varchar(8) COLLATE utf8_unicode_ci NOT NULL,
`DPH` int(11) unsigned NOT NULL,
`poradi` int(11) unsigned NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `DPH_2` (`DPH`),
UNIQUE KEY `popis` (`popis`),
KEY `DPH` (`DPH`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=9 ;