여러행을 하나의 컬럼으로 합치기

--가상 테이블

WITH TEST_TABLE AS (

    SELECT '고구려' COUNTRY, '1대' ST, '동명성왕'   KING_NM FROM DUAL UNION ALL

    SELECT '고구려' COUNTRY, '3대' ST, '대무신왕'   KING_NM FROM DUAL UNION ALL

    SELECT '백제'   COUNTRY, '1대' ST, '온조왕'     KING_NM FROM DUAL UNION ALL

    SELECT '고구려' COUNTRY, '2대' ST, '유리왕'     KING_NM FROM DUAL UNION ALL

    SELECT '백제'   COUNTRY, '3대' ST, '기루왕'     KING_NM FROM DUAL UNION ALL

    SELECT '신라'   COUNTRY, '2대' ST, '남해왕'     KING_NM FROM DUAL UNION ALL

    SELECT '신라'   COUNTRY, '1대' ST, '박혁거세'   KING_NM FROM DUAL UNION ALL

    SELECT '백제'   COUNTRY, '2대' ST, '다루왕'     KING_NM FROM DUAL UNION ALL

    SELECT '신라'   COUNTRY, '3대' ST, '유리이사금' KING_NM FROM DUAL

)

 

--조회 쿼리

SELECT COUNTRY

     , SUBSTR(  XMLAGG( XMLELEMENT(COL ,',', KING_NM) ORDER BY ST).EXTRACT('//text()' ).GETSTRINGVAL()  , 2) KING_NM

  FROM TEST_TABLE

 GROUP BY COUNTRY