php - 如何制作外键

Question

我正在尝试创建一个 sql create table 但我没有创建外键。

我的代码:

Db::getInstance()->execute('

      CREATE TABLE IF NOT EXISTS `'._DB_PREFIX_.'sondage`(
      `id` int(6) NOT NULL AUTO_INCREMENT,
      `question` varchar(60) NOT NULL,
      PRIMARY KEY(`id`)) ENGINE='._MYSQL_ENGINE_.' default CHARSET=utf8')

|| !Db::getInstance()->execute('

      CREATE TABLE IF NOT EXISTS `'._DB_PREFIX_.'sondage_reponse`(
      `id` int(6) NOT NULL AUTO_INCREMENT,
      `champ1` int(4) NOT NULL,
      `champ2` int(4) NOT NULL,
      `champ3` int(4) NOT NULL,
      PRIMARY KEY(`id`)) ENGINE='._MYSQL_ENGINE_.' default CHARSET=utf8')


|| !Db::getInstance()->execute('

 INSERT INTO '._DB_PREFIX_.'sondage_reponse (champ1,champ2,champ3)
 VALUES (0,0,0)')

我想从“sondage_reponse”中的“sondage”外键生成 id。我试过了:

 ALTER TABLE ps_sondage_reponse
            ADD FOREIGN KEY fk_id_sdg(id)
            REFERENCES sondage(id)')

但是 Prestashop 不能添加外键。

谢谢

Answer 1

我想试试这个:

ALTER TABLE ps_sondage_reponse
ADD CONSTRAINT FK_id_sdg
FOREIGN KEY (id) REFERENCES sondage(id)