程序艺术 2014-06-22
在代码中使用递归可能大部分程序员都不陌生,但是在存储过程或者函数中写个递归估计就不多见了。
今天遇到了一个在Oracle函数中使用递归的例子,特记录下来,方便以后查阅
CREATE OR REPLACE FUNCTION F_Func(v_pcatalogue IN NUMBER, i_newPcatalogue IN NUMBER, v_authTypeId in number)
RETURN NUMBER
as
v_newCatalogueId number(10);
v_oldCatalogueId number(10);
v_newPcatalogue number(10);
v_count number(10);
v_value number(10);
--根据目录表父节点ID查询目录表数据的游标
Cursor cusor_1(v_pcatalogue number) is
select id, cname, ename, cdescription, edescription, authtype, pcatalogue, orderb, createtime, userid, creater, updatetime, updateuserid, updator, state from t_catalogue
where authtype=v_authTypeId and pcatalogue=v_pcatalogue;
BEGIN
--记录下旧的父节点ID
v_oldCatalogueId := v_pcatalogue;
--记录下新的父节点ID
v_newPcatalogue := i_newPcatalogue;
select count(1) into v_count from t_catalogue where authtype=v_authTypeId and pcatalogue=v_pcatalogue;
if v_count = 0 then
return 1;
else
for c2 in cusor_1(v_oldCatalogueId) loop
--生成新的id及拷贝工作
v_oldCatalogueId := c2.id;
select HIBERNATE_SEQUENCE.NEXTVAL into v_newCatalogueId from dual;
if v_newPcatalogue is null then
select HIBERNATE_SEQUENCE.NEXTVAL into v_newPcatalogue from dual;
end if;
insert into t_catalogue_20140619(id, cname, ename, cdescription, edescription, authtype, pcatalogue, orderb, createtime, userid, creater, updatetime, updateuserid, updator, state)
values(v_newCatalogueId, c2.cname, c2.ename, c2.cdescription, c2.edescription, c2.authtype, v_newPcatalogue, c2.orderb, c2.createtime, c2.userid, c2.creater, c2.updatetime, c2.updateuserid, c2.updator, c2.state);
commit;
--不用变量接值,编译过不了
v_value := F_Func(v_oldCatalogueId, v_newCatalogueId, v_authTypeId);
end loop;
--这个返回很重要
return 1;
end if;
END F_Func;
/