1、爬樹：
with t as (
select '00' as code_child, '-1' as code_parent from dual
union
select '01' as code_child, '00' as code_parent from dual
union
select '02' as code_child, '01' as code_parent from dual
union
select '03' as code_child, '01' as code_parent from dual
union
select '04' as code_child, '03' as code_parent from dual
union
select '05' as code_child, '03' as code_parent from dual
union
select '06' as code_child, '03' as code_parent from dual
union
select '07' as code_child, '03' as code_parent from dual
)select * from t
start with t.code_child='03'
connect by prior t.code_child=t.code_parent --向下爬：找出所有子節點
--connect by prior t.code_parent=t.code_child --向上爬：找出所有父節點
;
2、將有分隔符的字串轉換為列表
a、程式塊
declare
p_codes varchar2(500);
begin
p_codes := '1,2,3,4,5,6';
for act in (select regexp_substr(p_codes, '[^,]+', 1, level) action_code
from dual
connect by level <=
length(p_codes) -
length(replace(p_codes, ',', '')) + 1) loop
dbms_output.put_line(act.action_code);
end loop;
null;
end;
b、sql語句
with t as
(select '1,2,3,4,5,6' as p_codes from dual)
select regexp_substr(t.p_codes, '[^,]+', 1, level) p_code
from t
connect by level <=
length(t.p_codes) - length(replace(t.p_codes, ',', '')) + 1;
3、oracle換行符：字串後拼chr(10) select 'testing'||chr(10)||"testing2" from dual;
4、匯出資料檔案相關指令碼：
a)新建sql檔案（本例的sql檔案為test.sql）
test.sql的內容格式如下：
set pagesize 0
set echo off
set feed off
set term off
set heading off
set trims off
set colsep '[分隔符]'
set linesize 500
set pagesize 2000
spool [輸出的檔案路徑]
[sql語句]
spool off
例子：set pagesize 0
set echo off
set feed off
set term off
set heading off
set trims off
set colsep '|'
set linesize 500
set pagesize 2000
spool d:\log\dbtest\test.txt
select * from t_cum_group;
spool off
b)在sqlplus命令窗下輸入：@[test.sql的所在檔案路徑]，例子：
@d:\log\dbtest\test.sql
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