Oracle中函数/历程返回结果集的几种方式

Oracle中函数/过程返回结果集的几种方式
转载地址：http://blog.csdn.net/feiliu010/archive/2007/03/23/1538822.aspx

Oracle中函数/过程返回结果集的几种方式:
    以函数return为例,存储过程只需改为out参数即可,在oracle 10g测试通过.
    (1) 返回游标:
        return的类型为:SYS_REFCURSOR
        之后在IS里面定义变量:curr SYS_REFCURSOR;
        最后在函数体中写:
         open cur for
            select ......;
         return cur;
        例:
      
CREATE OR REPLACE FUNCTION A_Test(
                orType varchar2
        )RETURN SYS_REFCURSOR
        is
               type_cur SYS_REFCURSOR;
        BEGIN
            OPEN type_cur FOR
                    select col1,col2,col3 from testTable ;
                  RETURN  type_cur;
        END;

    (2)返回table类型的结果集:
        首先定义一个行类型:
          
CREATE OR REPLACE TYPE "SPLIT_ARR"  AS OBJECT(nowStr varchar2(18))

        其次以此行类型定义一个表类型:
        
  CREATE OR REPLACE TYPE "SPLIT_TAB" AS TABLE of split_arr;

        定义函数(此函数完成字符串拆分功能):
          
CREATE OR REPLACE FUNCTION GetSubStr(
                   str in varchar2, --待分割的字符串
                   splitchar in varchar2 --分割标志
            )
            return split_tab
            IS
              restStr varchar2(2000) default GetSubStr.str;--剩余的字符串
              thisStr varchar2(18);--取得的当前字符串
              indexStr int;--临时存放分隔符在字符串中的位置
            
              v split_tab := split_tab(); --返回结果

            begin
                 dbms_output.put_line(restStr);
                 while length(restStr) != 0
                   LOOP
                     <<top>>
                     indexStr := instr(restStr,splitchar); --从子串中取分隔符的第一个位置

                     if indexStr = 0 and length(restStr) != 0  then--在剩余的串中找不到分隔符
                        begin
                          v.extend;
                          v(v.count) := split_arr(Reststr);
                          return v;
                        end;
                     end if;
                   
                     if indexStr = 1 then---第一个字符便为分隔符,此时去掉分隔符
                        begin
                             restStr := substr(restStr,2);
                             goto   top;
                        end;
                     end if;
                   
                     if length(restStr) = 0 or restStr is null then
                        return v;
                     end if;
                  
                     v.extend;
                     thisStr := substr(restStr,1,indexStr - 1); --取得当前的字符串
                     restStr := substr(restStr,indexStr + 1);---取剩余的字符串

                     v(v.count) := split_arr(thisStr);
                   END LOOP;
                 return v;
            end;

        在PL/SQL developer中可以直接调用
         
cursor strcur is
                         select nowStr from Table(GetSubStr('111,222,333,,,',','));

    (3)以管道形式输出:
      
create type row_type as object(a varchar2(10), v varchar2(10));--定义行对象
        create type table_type as table of row_type; --定义表对象
        create or replace function test_fun(
            a in varchar2,b in varchar2
        )
        return table_type pipelined
        is
            v row_type;--定义v为行对象类型
        begin
          for thisrow in (select a, b from mytable where col1=a and col2 = b) loop
            v := row_type(thisrow.a, thisrow.b);
            pipe row (v);
          end loop;
          return;
        end;
        select * from table(test_fun('123','456'));