Database version: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
First, create test data:
create table test(id number,name varchar2(20));
insert into test values(1,'a');
insert into test values(1,'b');
insert into test values(1,'c');
insert into test values(2,'d');
insert into test values(2,'e');
Second, multiple rows of data aggregation
2.1 wm_concat
SELECT ID,
to_char(wm_concat('['||NAME||ID||']')) colname
FROM TEST GROUP BY ID
2.2 LISTAGG
SELECT ID,
listagg(NAME,'$') WITHIN GROUP(ORDER BY NAME) OVER(PARTITION BY ID) colname
FROM TEST
SELECT ID,
listagg(NAME,'$') WITHIN GROUP(ORDER BY NAME) colname
FROM TEST
GROUP BY ID
See detailed syntax oracle official website: click the link to open