ORACLE 行转列的通用过程

--测试数据
create table rowtocol_test as
select 2009 year,1 month,'部门1' dept,50000 expenditure from dual
union all select 2009,2,'部门1',20000 from dual
union all select 2009,2,'部门1',30000 from dual
union all select 2010,1,'部门1',35000 from dual
union all select 2009,2,'部门2',40000 from dual
union all select 2009,3,'部门2',25000 from dual
union all select 2010,2,'部门3',60000 from dual
union all select 2009,2,'部门3',15000 from dual
union all select 2009,2,'部门3',10000 from dual;

--建存储过程 返回游标
create or replace function row_to_col_func(tabname in varchar2,
group_col in varchar2,
column_col in varchar2,
value_col in varchar2,
Aggregate_func in varchar2 default 'max',
colorder in varchar2 default null,
roworder in varchar2 default null,
when_value_null in varchar2 default null
)return sys_refcursor
Authid Current_User
as
/*
参数:
tabname 需要进行行转列操作的表名;
group_col 查询结果要按某列或某些列分组的字段名;
column_col 要从行转成列的字段;
value_col 需要聚合的值字段;
Aggregate_func 选用的聚合函数,可选,默认为max;
colorder 行转列后列的排序,可选;
roworder 行转列后记录的排序,可选;
when_value_null 若value_col字段的值聚合后为空,则转换成该值,可选;
--viewname 创建的视图名称,可选,默认为v_tmp。
*/
sqlstr varchar2(2000):='select '||group_col||' ';
c1 sys_refcursor;
v1 varchar2(100);
cur sys_refcursor;
begin
open c1 for 'select distinct '||column_col||' from '||tabname||case when colorder is not null then ' order by '||colorder end;
loop
fetch c1 into v1;
exit when c1%notfound;
sqlstr:=sqlstr||chr(10)||','||case when when_value_null is not null then 'nvl(' end||
Aggregate_func||'(decode(to_char('||column_col||'),'''||v1||''','||value_col||'))'||
case when when_value_null is not null then chr(44) ||when_value_null||chr(41) end||'"'||v1||'"';
end loop;
close c1;
open cur for sqlstr||' from '||tabname||' group by '||group_col||case when roworder is not null then ' order by '||roworder end;
return cur;
end row_to_col_func;

--
select row_to_col_func('rowtocol_test','year,month','dept','expenditure',Aggregate_func => 'sum',colorder => 'dept',roworder => '1,2',when_value_null => '0')
from dual;

转自:http://bbs.csdn.net/topics/330039676

原文地址:https://www.cnblogs.com/kenwong/p/3976643.html