sql内连接单表

Question

三列表格； ID、术语、同义词

1, IDENTITY, CHARACTER
2, IDENTITY, EXISTENCE
3, IDENTITY, IDENTIFICATION
4, IDENTITY, INTEGRITY 
5, IDENTITY, NAME
6, CIRCUMSTANCES, ASSETS
7, CIRCUMSTANCES, CAPITAL
8, CIRCUMSTANCES, CHANCES

我需要结果返回具有关联“同义词”的不同“术语”，消除多对多并返回一对多作为结果。

1, IDENTITY, CHARACTER | EXISTENCE | IDENTIFICATION | INTEGRITY | NAME
6, CIRCUMSTANCES, ASSETS |CAPITAL | CHANCES

或者，

1、TERM="IDENTITY" SYNONYM="CHARACTER" SYNONYM="EXISTENCE" SYNONYM="IDENTIFICATION" SYNONYM="INTEGRITY" SYNONYM="NAME"

2、TERM="CIRCUMSTANCES" SYNONYM="ASSETS" SYNONYM="CAPITAL" SYNONYM="CHANCES"

Answer 1

如果你使用 MySQL，可以使用GROUP_CONCAT

SELECT MIN(`ID`), `TERM`, GROUP_CONCAT(`SYNONYM`, ' | ') 
FROM my_table
GROUP BY `TERM`;

Answer 2

Oracle 解决方案 - 从 11g 开始：

with sample as
(
  select 1 ID,  'IDENTITY' term , 'CHARACTER' syn from dual
  union all
  select 2, 'IDENTITY', 'EXISTENCE' from dual 
  union all
  select 3, 'IDENTITY', 'IDENTIFICATION' from dual 
  union all
  select 4, 'IDENTITY', 'INTEGRITY' from dual 
  union all
  select 5, 'IDENTITY', 'NAME' from dual 
  union all
  select 6, 'CIRCUMSTANCES', 'ASSETS' from dual 
  union all
  select 7, 'CIRCUMSTANCES', 'CAPITAL' from dual 
  union all
  select 8, 'CIRCUMSTANCES', 'CHANCES' from dual 
)
select  min(id) id, term,
listagg(syn,'|') within group(order by syn) syns
from sample
group by term;

输出：

      ID TERM          SYNS
---------- ------------- ------------------------------------------------------
         6 CIRCUMSTANCES ASSETS|CAPITAL|CHANCES
         1 IDENTITY      CHARACTER|EXISTENCE|IDENTIFICATION|INTEGRITY|NAME