[POSTGRES] 여러개의 행 하나의 행으로 표현하기

위 사진처럼 여러개의 행을 하나의 행으로 표현하기

 

with school as (
	select '1' as grade,'1' as class, '홍길동(1)' as name, 70 as score from dual union all 
    select '1','1','홍길동(4)',10 from dual union all
	select '2','1','홍길동(5)',50 from dual union all
    select '2','1','홍길동(7)', 15 from dual union all
    select '2','2','홍길동(8)',90 from dual union all
    select '3','1','홍길동(2)',54 from dual union all
    select '3','1','홍길동(6)',60 from dual union all
	select '3','2','홍길동(3)',72 from dual union all
    select '3','2','홍길동(9)',0 from dual 
)   SELECT array_to_string(array_agg(name),',') from school;

 

// array_to_string(array_agg('컬럼명'),'구분자')
select array_to_string(array_agg(column),',')  from daul;

 

출처 : https://good4uprin.tistory.com/36