Question

我有一个交叉引用表，其中包含两个外键。 RoleId（PK，FK）和PermissionId（PK，FK）。 Role表和Permission表都包含名为ApplicationId的外键列。我想确保无法将记录插入到交叉引用表中，该交叉引用表包含与ApplicationId 1关联的RoleId和与ApplicationId关联的PermissionId 2.除了使用触发器实现此类完整性之外，还有其他方法吗？

Answer 1

您可以将applicationId列添加到交叉引用表中，然后扩展Role和Permission表的外键以包含applicationId列。这提供了所需的参照完整性。

这是mysql中已解决的架构

CREATE TABLE `application` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

CREATE TABLE `permission` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `applicationId` int(11) unsigned NOT NULL,
  PRIMARY KEY (`id`),
  KEY `id_app` (`id`,`applicationID`),
  CONSTRAINT `FK_perm_app` FOREIGN KEY (`applicationID`) REFERENCES `application` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

CREATE TABLE `role` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `applicationId` int(11) unsigned NOT NULL,
  PRIMARY KEY (`id`),
  KEY `id_app` (`id`,`applicationID`),
  CONSTRAINT `FK_role_app` FOREIGN KEY (`applicationID`) REFERENCES `application` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

CREATE TABLE `role_permission_application` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `roleID` int(11) unsigned NOT NULL,
  `permissionID` int(11) unsigned NOT NULL,
  `applicationID` int(11) unsigned NOT NULL,
  PRIMARY KEY (`id`),
  KEY `FK_role` (`roleID`,`applicationID`),
  KEY `FK_permission` (`permissionID`,`applicationID`),
  CONSTRAINT `FK_permission` FOREIGN KEY (`permissionID`,`applicationID`) REFERENCES `permission`  (`id`,`applicationID`),
  CONSTRAINT `FK_role` FOREIGN KEY (`roleID`,`applicationID`) REFERENCES `role` (`id`,`applicationID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

交叉引用表上的约束，它将检查主键表列的完整性

1 个答案: