Question

我有两个表主题和评估主题表是具有ID和名称的基本表，并且在评估表中有一个名为topic_list的json列，存储主题数组，我需要具有ID的特定评估的主题列表和名字

CREATE TABLE `topics` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `name` varchar(255) NOT NULL COMMENT 'topic name will capture here',
   PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=latin1



CREATE TABLE `assessments` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `topic_list` json DEFAULT NULL,
   `assessment_name` varchar(150) DEFAULT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=latin1




INSERT INTO `topics` (name) values ('topic1'),('topic2'),('topic3');

INSERT INTO `assessments` (topic_list, assessment_name) values ('[1,2]','assessment1'),('[2,3]', 'assessment2'),('[1,3]', 'assessment3');



SELECT t1.id,t1.name FROM topics AS t1 WHERE id IN (SELECT topic_list FROM assessments WHERE id = 1)

这是我尝试过的，但只是获得第一行

SELECT id,name from topics where id in(select JSON_UNQUOTE(TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM JSON_EXTRACT(topic_list, '$[*]')))) from assessments where id = 1)

我得到的是

1   topic1

结果仅是数组的第一列

我正在尝试

1   topic1
2   topic2

Answer 1

您可以通过JSON_EXTRACT和JSON_CONTAINS使用以下解决方案：

SELECT id, name 
FROM topics WHERE (
    SELECT JSON_CONTAINS(
        JSON_EXTRACT(topic_list, '$[*]'), 
        CONVERT(topics.id, JSON)
    ) FROM assessments WHERE id = 1
);

演示： https://www.db-fiddle.com/f/9Ag2dZHR5UPwd8p5EaP2LE/2

如何从一个表中选择列，而另一表的json列中的id

1 个答案: