Oracle 实现字符串相加 函数

http://lwl0606.cmszs.com/archives/oracle-string-add-function.html

有如下表，实现相同Account 的DSPNAME值相加
Account DSPNAME
L1 aa
L1 bb
L2 cc
结果L1 aa,bb

L2 cc

方法1：在函数中使用cursor

CREATE OR REPLACE FUNCTION SDA.FNROLE (ACC in varchar2)
return varchar2 is
Result varchar2(500);
cursor rad_cursor is
select DSPNAME from SDA_USER_ROLE
where LOWER(Account) =LOWER(ACC);
begin
for rad_val in rad_cursor
loop
Result:=Result ||','|| rad_val.DSPNAME;
end loop;
RESULT:=SUBSTR(Result,2);
return(Result);
end FNROLE;

使用select sda.fnrole('1') AS A from dual;

方法2：使用oracle分析函数 转 自 miclu

City People Make
广州 1 A
广州 2 B
广州 3 C
上海 4 A
上海 5 E
广州 6 A
上海 7 E

select City,sum(People) as People,ZH_SPLIT(ltrim(max(sys_connect_by_path(Make,',')),','),',') as Make
from (
select City,People,Make,
rank()over(order by City) + row_number()over(order by City) RN,
row_number()over(partition by City order by City) RM
from SRS_B_CW_TEST
)
start with RM=1
connect by prior RN=RN-1
group by
City

写一个函数去除重复值
/************************************************************************************
创建者：曾浩
创建时间：2007-9-27
最新修改者：曾浩
最新修改时间：2007-9-27
用途：改进的split函数,
输入字符串123,123,234,345,234,345,456和字符串,
输出123,234,345,456
************************************************************************************/
create or replace function ZH_SPLIT(v_string in varchar2, v_delimiter in varchar2)
return varchar2
is
j int:=0;
i int:=1;
len_string int:=0;
len_delimiter int:=0;
str varchar2(4000);
v_return varchar2(4000);
begin
len_string := LENGTH(v_string);
len_delimiter := LENGTH(v_delimiter);
while j < len_string
loop
j := INSTR(v_string, v_delimiter, i);
if j = 0 then
j := len_string;
str := SUBSTR(v_string, i);
if instr(v_return, str) > 0 then
null;
else
v_return:=v_return||str||',';
end if;
if i >= len_string then
exit;
end if;
else
str := SUBSTR(v_string, i, j - i);
i := j + len_delimiter;
if instr(v_return, str) > 0 then
null;
else
v_return:=v_return||str||',';
end if;
end if;
end loop;
v_return := substr(v_return, 1, length(v_return)-1);
return v_return;
end;

方法3：如果ID列为数字，可免去去除重复值的函数

create table TEST AS
(select 1 ID, '11111' MC from dual
union
select 1, '22222'from dual
union
select 2, '11111'from dual
union
select 2, '22222'from dual
union
select 3, '11111'from dual
union
select 3, '22222'from dual
union
select 3, '33333'from dual );

select id,ltrim(max(sys_connect_by_path(mc,',')),',') row2col
from (select id,mc,
ID+(row_number() over(order by id)) node_id,
row_number() over(partition by id order by id) rn
from test)
start with rn = 1
connect by node_id-1 = prior node_id
group by id
order by id;

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