oracle的wm_concat函数实现行转列

有以下数据

deptname	phone	username	isboss
部门A	电话1	员工A	0
部门A	电话1	领导A	1
部门B	电话2	员工B	0
部门B	电话2	员工C	0
部门B	电话2	领导D	1

需要展示效果

deptname	phone	boss	emp
部门A	电话1	领导A	员工A
部门B	电话2	领导D	员工B,员工C

因为是oracle10g的原因,所以使用了wm_concat函数,但对wm_concat结果长度有限制,超出会报ORA-22922:不存在的LOB值,这是后话,先贴代码

Select t5.deptname,
       Max(t5.tel),
       dbms_lob.substr(wmsys.wm_concat(To_Char(t5.boss))) boss,
       dbms_lob.substr(wmsys.wm_concat(To_Char(t5.notboss))) notboss
  From (Select t1.NAME deptname,
               t1.TEL tel,
               Case t2.ISBOSS
                 When 1 Then
                  t2.TRUE_NAME
               End boss,
               Case t2.ISBOSS
                 When 0 Then
                  t2.TRUE_NAME
               End notboss
          From t_duty t
          Left Join t_department t1
            On t.DEP_ID = t1.DEP_ID
          Left Join t_contacts t2
            On t.CONTACTS_ID = t2.CONTACTS_ID
         Where t.DUTY_TIME = Trunc(SysDate) ) t5
 Group By t5.deptname

同样的情况的如果是oracle11gR2版本可以用LISTAGG函数,据说可以解决上面的报错问题,这个有待以后测试

但是我现在的是10g的,而且会报上面的错误,网上的一些解决方案都没解决,有人写了自定义函数,亲测完美解决

原出处已经找不到了,就不贴链接了,但还是非常感谢解决了这个问题

create or replace TYPE zh_concat_im
AUTHID CURRENT_USER AS OBJECT
(
  CURR_STR VARCHAR2(32767),
  STATIC FUNCTION ODCIAGGREGATEINITIALIZE(SCTX IN OUT zh_concat_im) RETURN NUMBER,
  MEMBER FUNCTION ODCIAGGREGATEITERATE(SELF IN OUT zh_concat_im,
               P1 IN VARCHAR2) RETURN NUMBER,
  MEMBER FUNCTION ODCIAGGREGATETERMINATE(SELF IN zh_concat_im,
                                 RETURNVALUE OUT VARCHAR2,
                                 FLAGS IN NUMBER)
                     RETURN NUMBER,
  MEMBER FUNCTION ODCIAGGREGATEMERGE(SELF IN OUT zh_concat_im,
                    SCTX2 IN  zh_concat_im) RETURN NUMBER
);
/
create or replace TYPE BODY zh_concat_im
IS
  STATIC FUNCTION ODCIAGGREGATEINITIALIZE(SCTX IN OUT zh_concat_im)
  RETURN NUMBER
  IS
  BEGIN
    SCTX := zh_concat_im(NULL) ;
    RETURN ODCICONST.SUCCESS;
  END;
  MEMBER FUNCTION ODCIAGGREGATEITERATE(SELF IN OUT zh_concat_im,
          P1 IN VARCHAR2)
  RETURN NUMBER
  IS
  BEGIN
    IF(CURR_STR IS NOT NULL) THEN
      CURR_STR := CURR_STR || ':' || P1;
    ELSE
      CURR_STR := P1;
    END IF;
    RETURN ODCICONST.SUCCESS;
  END;
  MEMBER FUNCTION ODCIAGGREGATETERMINATE(SELF IN zh_concat_im,
                                 RETURNVALUE OUT VARCHAR2,
                                 FLAGS IN NUMBER)
    RETURN NUMBER
  IS
  BEGIN
    RETURNVALUE := CURR_STR ;
    RETURN ODCICONST.SUCCESS;
  END;
  MEMBER FUNCTION ODCIAGGREGATEMERGE(SELF IN OUT zh_concat_im,
                                   SCTX2 IN zh_concat_im)
  RETURN NUMBER
  IS
  BEGIN
    IF(SCTX2.CURR_STR IS NOT NULL) THEN
      SELF.CURR_STR := SELF.CURR_STR || ':' || SCTX2.CURR_STR ;
    END IF;
    RETURN ODCICONST.SUCCESS;
  END;
END;
/
create or replace FUNCTION zh_concat(P1 VARCHAR2)
RETURN VARCHAR2 AGGREGATE USING zh_concat_im ;
/