无法添加外键MySQL：errno 150

Question

我尝试添加外键：

   CREATE TABLE `invoices` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
  ` name` varchar(255) NOT NULL,
   `code_text` text NOT NULL,
   PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;




  CREATE TABLE `leads` (
  `lead_id` int(11) NOT NULL AUTO_INCREMENT,
   ...
   PRIMARY KEY (`lead_id`)
  );



CREATE TABLE `leads_invoices` (
leads_invoice_id int(11) AUTO_INCREMENT NOT NULL,
   invoice_id int(11) NOT NULL,
   lead_id_i  int(11) NOT NULL,
   PRIMARY KEY(leads_invoice_id),
    FOREIGN KEY (invoice_id) REFERENCES invoices(id),
    FOREIGN KEY (lead_id_i) REFERENCES leads(lead_id)
    ON UPDATE CASCADE
    ON DELETE RESTRICT
) ENGINE=InnoDB DEFAULT CHARSET=utf8

但是我的lead_id_i键出错：

无法创建表crm_test 。 leads_invoices （错误号：150“外键约束leads_invoices不正确”）

我检查了所有类型和表，看来它们是正确的。如何解决此问题？ 希望你能帮助我。 谢谢！

Answer 1

您必须将ENGINE=InnoDB DEFAULT CHARSET=utf8到销售线索表中

CREATE TABLE `leads` (
  `lead_id` int(11) NOT NULL AUTO_INCREMENT,
   ...
   PRIMARY KEY (`lead_id`)
  )ENGINE=InnoDB DEFAULT CHARSET=utf8;

因为如果要添加外键，则两个表必须具有相同的引擎