mysql - 将模式字符串拆分为选择查询中的列

Question

我有一个具有以下结构的 person 表。

CREATE TABLE person(id integer, details LONGTEXT);
INSERT INTO person(id,details) 
VALUES
(1, "name:Tahir,age:30,sex:male"),
(2, "name:Tina,sex:female,status:1");

问题: 我对数据库端有一些限制，无法添加新表/列，因此必须临时使用 LONGTEXT 详细信息的可用列。所以，我没有其他办法，只能寻找解决方法。

所以，我想用逗号分割详细信息列，并在不同的列中显示结果。例如，在此示例中，结果将是 id、姓名、年龄、性别、状态

我相信聚合函数可以实现这一点，并且我尝试生成如下所示的查询

SELECT id,
if(person.details like '%name:%',cast(substring_index(substring_index(person.details,'name:',-1),',',1) as unsigned),null) as `name`,
if(person.details like '%age:%',cast(substring_index(substring_index(person.details,'age:',-1),',',1) as unsigned),null) as `age`,
if(person.details like '%sex:%',cast(substring_index(substring_index(person.details,'sex:',-1),',',1) as unsigned),null) as `sex`,
if(person.details like '%status:%',cast(substring_index(substring_index(person.details,'status:',-1),',',1) as unsigned),null) as `status`
FROM person

上面的查询正确获取了年龄数据，但姓名和性别为 0。您能弄清楚我在这里缺少什么吗？

https://www.db-fiddle.com/f/cqyqb7Vhvs7kKYifFywmkV/6

Answer 1

您正在将明显的字符串转换为无符号(整数)。无需转换:

SELECT
  id,
  if(person.details like '%name:%',substring_index(substring_index(person.details,'name:',-1),',',1),null) as `name`,
  if(person.details like '%age:%',cast(substring_index(substring_index(person.details,'age:',-1),',',1) as unsigned),null) as `age`,
  if(person.details like '%sex:%',substring_index(substring_index(person.details,'sex:',-1),',',1),null) as `sex`
FROM person