存储过程返回结果集

存储过程返回OUT参数的游标
例子：每个学生求平均值的存储过程。
遇到的问题是带参数游标中的变量名字不要和表中的一样，否则会出问题

create or replace procedure AAA   
as    
--查询学生表的ID   
cursor s_sno is select s.sno from student s;    
--通过学生ID查询平均成绩   
cursor sc_avg(s_no varchar2) is select avg(sc.degree) from score sc where sc.sno=s_no;    
s_sno_j student.sno%type;   --变量ID   
sc_avg_i score.degree%type; --变量平局成绩   
begin  
 open s_sno;--打开查询ID的游标   
 loop   
   fetch s_sno into s_sno_j;   
   exit when s_sno%notfound;     
     open sc_avg(s_sno_j); --打开查询平均成绩的游标，参数为学生ID   
     loop   
     fetch sc_avg into sc_avg_i;   
     exit when sc_avg%notfound;   
     dbms_output.put_line(sc_avg_i);   
     end loop;   
     close sc_avg;   
 end loop;   
 close s_sno;   
end AAA;  

###############################################################################################
包中带过程 要自己定义一个type [cur_name] is ref cursor游标，返回的时候就直接 procedure AAA(变量名 out [cur_name])如此申明OUT变量
存储过程 用系统默认的 sys_refcursor 游标类型 定义变量就OK了
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--PL/SQL Code(存储过程) 带游标的OUT参数，返回游标(ref cursor)   
    
create or replace procedure retCursor(ret_cursor out sys_refcursor)is  
ret_cursor_value  sys_refcursor;   
begin  
open ret_cursor_value for select * from student;   
 ret_cursor:=ret_cursor_value;   
end retCursor;  

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Class.forName("oracle.jdbc.driver.OracleDriver");   
Connection conn = Connection conn = DriverManager.getConnection                       ("jdbc:oracle:thin:@XX.XX.XX.XXX:XXXX:oracle9i","XXX_temp","XXX_temp");    
  
DriverManager.registerDriver (new oracle.jdbc.OracleDriver());      
CallableStatement cs = conn.prepareCall("{ call retCursor(?) }");   
cs.registerOutParameter(1,OracleTypes.CURSOR);   
cs.execute();   
ResultSet rs = ((OracleCallableStatement)cs).getCursor(1);   
while(rs.next())   
{   
    System.out.println(rs.getString(1)+"  "+rs.getString(2)+"  "+rs.getString(3)+"  "+ rs.getDate(4)+"  "+rs.getString(5));   
} 

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--PL/SQL Code (包中带过程) 过程带游标的OUT参数，返回游标(ref cursor)   
  
create or replace package my_pack as  
 type my_ref_cursor is ref cursor;   
 procedure getMyCursor(val out my_ref_cursor);    
end my_pack;   
  
create or replace package body my_pack as  
 procedure getMyCursor(val out my_ref_cursor)   
 is  
 begin  
  open val for select * from student;   
 end;   
end my_pack;   

Class.forName("oracle.jdbc.driver.OracleDriver");   
Connection conn = DriverManager.getConnection                     ("jdbc:oracle:thin
:@XX.XX.XX.XXX:XXXX:oracle9i","XXX_temp","XXX_temp");    
DriverManager.registerDriver (new oracle.jdbc.OracleDriver());      
CallableStatement cs = conn.prepareCall("{ call my_pack.getMyCursor(?) }");   
cs.registerOutParameter(1,OracleTypes.CURSOR);   
cs.execute();   
ResultSet rs = ((OracleCallableStatement)cs).getCursor(1);   
while(rs.next())   
{   
    System.out.println(rs.getString(1)+"  "+rs.getString(2)+"  "+rs.getString(3)+"  "+ rs.getDate(4)+"  "+rs.getString(5));   
} 

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