Mysql 行中的 table 行移动并合并到命名列中

Question

我有以下数据

drop table if exists states;
create table states (id integer, state varchar(100), content varchar(100));
insert into states (id, state, content) values (1, 'soc', '73');
insert into states (id, state, content) values (2, 'range', '412');
insert into states (id, state, content) values (3, 'range', '410');
insert into states (id, state, content) values (3, 'soc', '71');
insert into states (id, state, content) values (5, 'range', '405');

使用以下语句

SELECT id,
       CASE WHEN state = 'range' THEN content ELSE null END AS 'range',
       CASE WHEN state = 'soc' THEN content ELSE null END AS 'soc'
FROM states;

结果是

id	范围	社会
1		73
2	412
3	410
3		71
5	405

但我想将id为3的两行合并为一行

id	范围	社会
1		73
2	412
3	410	71
5	405

必须改变什么才能达到预期的结果？

Answer 1

SELECT id,
       CASE WHEN state = 'range' THEN content ELSE null END AS 'range',
       CASE WHEN state = 'soc' THEN content ELSE null END AS 'soc'
FROM states;

id	range	soc
1	null	73
2	412	null
3	410	null
3	null	71
5	405	null

SELECT id,
       MAX(CASE WHEN state = 'range' THEN content END) AS 'range',
       MAX(CASE WHEN state = 'soc' THEN content END) AS 'soc'
FROM states
GROUP BY id;

id	range	soc
1	null	73
2	412	null
3	410	71
5	405	null

db<>fiddle here

Mysql 行中的 table 行移动并合并到命名列中

Mysql rows from one table moved and merged into named columns

mysql

sql

case