根据表中的行创建一个分隔列表

6.10 根据表中的行创建一个分隔列表

---要求将emp表中的ename，用逗号间隔合并在一起显示。如：CLARK,KING,MILLER

listagg:

把字符串连在一起

SELECT deptno,
       SUM(sal) AS total_sal,
       listagg(ename, ',') within GROUP(ORDER BY ename) AS totoal_ename
  FROM emp
 GROUP BY deptno;


listagg(ename, ',')   第一个参数 第2个是分隔符(自定义)


within GROUP(ORDER BY ename 当前分组内

SQL>  SELECT empno,
  2         ename,
  3         deptno,
  4         sal,
  5         SUM(sal) over(PARTITION BY deptno) AS total_sal,
  6         listagg(ename, ',') within GROUP(ORDER BY ename) over(PARTITION BY deptno) AS total_ename
  7    FROM emp
  8   WHERE deptno IN (10, 20);

     EMPNO ENAME          DEPTNO        SAL  TOTAL_SAL TOTAL_ENAME
---------- ---------- ---------- ---------- ---------- ------------------------------
      7782 CLARK              10       2450       8750 CLARK,KING,MILLER
      7839 KING               10       5000       8750 CLARK,KING,MILLER
      7934 MILLER             10       1300       8750 CLARK,KING,MILLER
      7876 ADAMS              20       1100      10875 ADAMS,FORD,JONES,SCOTT,SMITH
      7902 FORD               20       3000      10875 ADAMS,FORD,JONES,SCOTT,SMITH
      7566 JONES              20       2975      10875 ADAMS,FORD,JONES,SCOTT,SMITH
      7788 SCOTT              20       3000      10875 ADAMS,FORD,JONES,SCOTT,SMITH
      7369 SMITH              20        800      10875 ADAMS,FORD,JONES,SCOTT,SMITH

已选择8行。

主查询不分组的时候，分析函数取分组的数据