mysql - 如何从索引到另一个表行的行中获取数据？

Question

嗨，我有这样的 mysql 表：

.poll_users
(id int(11) NOT NULL AUTO_INCREMENT
name VARCHAR(255) NOT NULL
PRIMARY KEY (id))

.poll_referendum
        (id int(11) NOT NULL AUTO_INCREMENT
        name varchar(255) DEFAULT NULL
        PRIMARY KEY (id))

.poll_questions 
     id int(11) NOT NULL AUTO_INCREMENT
    referendum_id int(11) DEFAULT NULL
    body varchar(255) DEFAULT NULL
    created_at datetime DEFAULT NULL
    updated_at datetime DEFAULT NULL
    PRIMARY KEY (`id`)
    KEY `referendum_id` (`referendum_id`))

.poll_answers 
 `id` int(11) NOT NULL AUTO_INCREMENT
 `vote_id` int(11) DEFAULT '0'
 `question_id` int(11) NOT NULL
 `created_at` datetime DEFAULT NULL
 `updated_at` datetime DEFAULT NULL
 PRIMARY KEY (`id`)
 KEY `vote_id` (`vote_id`)
 KEY `question_id` (`question_id`))

.poll_voting 
    `id` int(11) NOT NULL AUTO_INCREMENT
    `question_id` int(11) NOT NULL DEFAULT '0'
    `answer_id` int(11) NOT NULL DEFAULT '0'
    `user_id` int(11) NOT NULL DEFAULT '0'
    `created_at` datetime DEFAULT NULL
    `updated_at` datetime DEFAULT NULL
    PRIMARY KEY (`id`)
    KEY `question_id` (`question_id`)
    KEY `answer_id` (`answer_id`)
    KEY `user_id` (`user_id`))

.vote_types 
    `id` int(11) NOT NULL AUTO_INCREMENT
    `type` varchar(255) DEFAULT NULL
    PRIMARY KEY (`id`))

如何获取 vote_types 表中的投票类型并对应于正确的问题和调查？

我试过了：SELECT vote_id FROM surveys.poll_answers WHERE question_id = 1; 但这给了我：

和 1,2 是投票类型文本SELECT * FROM调查的索引.vote_types WHEREid=1 在 poll_answers 表中，我保留索引哪些投票类型分配给问题，问题分配给 poll_referendum 表中的适当公投，所以我如何获取与正确问题相对应的投票类型和像这样的调查

SELECT vote_id indexes from poll_answers table and they index to vote_types where are stored vote types in text and those vote_types corresponds to proper questions that are stored in poll_questions and referendums that are stored in poll_referendum ? 

谢谢你的帮助

Answer 1

我不确定。也许您正在谈论表连接。

SELECT 
           v.*
      FROM poll_answers AS a
      INNER JOIN poll_voting AS v ON (v.id=a.vote_id)
      WHERE a.question_id = 1;