再发 行转列通用过程
本帖最后由 wildwave 于 2010-01-20 20:17:41 编辑 之前发过一个帖子，叫行转列的通用过程，http://topic.csdn.net/u/20091019/11/67cd55a3-3f42-4db7-a3f8-91dd52a913cd.html能满足最基本的需求。但也有一些缺陷，现在对其进行完善
代码
1.使用视图
create or replace procedure row_to_col(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,
viewname in varchar2 default 'v_tmp')
Authid Current_User
as
sqlstr varchar2(2000):='create or replace view '||viewname||' as select '||group_col||' ';
c1 sys_refcursor;
v1 varchar2(100);
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;
sqlstr:=sqlstr||' from '||tabname||' group by '||group_col||case when roworder is not null then ' order by '||roworder end;
execute immediate sqlstr;
end row_to_col;
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。
举例：
--测试数据我现在想根据year和month分组，将部门转成列。
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;
SQL> select * from rowtocol_test;
YEAR MONTH DEPT EXPENDITURE
---------- ---------- ----- -----------
2009 1 部门1 50000
2009 2 部门1 20000
2009 2 部门1 30000
2010 1 部门1 35000
2009 2 部门2 40000
2009 3 部门2 25000
2010 2 部门3 60000
2009 2 部门3 15000
2009 2 部门3 10000
9 rows selected
SQL> execute row_to_col('rowtocol_test','year,month','dept','expenditure');
PL/SQL procedure successfully completed
SQL> select * from v_tmp;
YEAR MONTH 部门1 部门3 部门2
---------- ---------- ---------- ---------- ----------
2009 1 50000
2010 1 35000
2009 3 25000
2009 2 30000 15000 40000
2010 2 60000
SQL>
SQL> execute row_to_col('rowtocol_test','year,month','dept','expenditure',Aggregate_func => 'sum',colorder => 'dept',roworder => '1,2',when_value_null => '0');
PL/SQL procedure successfully completed
SQL> select * from v_tmp;
YEAR MONTH 部门1 部门2 部门3
---------- ---------- ---------- ---------- ----------
2009 1 50000 0 0
2009 2 50000 40000 25000
2009 3 0 25000 0
2010 1 35000 0 0
2010 2 0 0 60000
SQL> SQL> create view view_rowtocol as select * from rowtocol_test where year=2009;
View created
SQL> execute row_to_col('view_rowtocol','year,month','dept','expenditure',Aggregate_func => 'sum',colorder => 'dept',roworder => '1,2',when_value_null => '0');
PL/SQL procedure successfully completed
SQL> select * from v_tmp;
YEAR MONTH 部门1 部门2 部门3
---------- ---------- ---------- ---------- ----------
2009 1 50000 0 0
2009 2 50000 40000 25000
2009 3 0 25000 0
SQL>
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
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;
ROW_TO_COL_FUNC('ROWTOCOL_TEST
<Cursor>
YEARMONTH部门1部门2部门3
20091500000 0
20092500004000025000
200930 250000
20101350000 0
201020 0 60000
