I have a table with values as follows:
SQL> SELECT deptno, ename FROM emp ORDER BY deptno, ename;
DEPTNO ENAME
------ ----------
10 CLARK
10 KING
10 MILLER
20 ADAMS
20 FORD
20 JONES
20 SCOTT
20 SMITH
30 ALLEN
30 BLAKE
30 JAMES
30 MARTIN
30 TURNER
30 WARD
14 rows selected.
but I need them in the following less convenient format:
DEPTNO ENAME
------ -----------------------------------------
10 CLARK, KING, MILLER
20 ADAMS, FORD, JONES, SCOTT, SMITH
30 ALLEN, BLAKE, JAMES, MARTIN, TURNER, WARD
The following example illustrates the technique using the SCOTT demo table "emp":2
SELECT deptno
, LTRIM(SYS_CONNECT_BY_PATH(ename,','))
FROM ( SELECT deptno, ename
, ROW_NUMBER() OVER (PARTITION BY deptno ORDER BY ename) -1 AS seq
FROM emp )
WHERE connect_by_isleaf = 1
CONNECT BY seq = PRIOR seq +1 AND deptno = PRIOR deptno
START WITH seq = 1;
DEPTNO CONCATENATED
---------- --------------------------------------------------
10 CLARK,KING,MILLER
20 ADAMS,FORD,JONES,SCOTT,SMITH
30 ALLEN,BLAKE,JAMES,MARTIN,TURNER,WARD
3 rows selected.
Another approach involves harnessing the dark power of XML:3
SELECT deptno
, RTRIM
( xmlagg (xmlelement (c, ename || ',') order by ename).extract ('//text()')
, ',' ) AS concatenated
FROM emp
GROUP BY deptno;
DEPTNO CONCATENATED
---------- ---------------------------------------------------------------
10 CLARK,KING,MILLER
20 ADAMS,FORD,JONES,SCOTT,SMITH
30 ALLEN,BLAKE,JAMES,MARTIN,TURNER,WARD
3 rows selected.
