Oracle (iii) a stored procedure with a cursor

--创建或修改存储过程，存储过程名为findclass,输入参数为classId,输出className
create or replace procedure findclass(classId in int,classStudents out sys_refcursor,className out varchar2)
as
--定义一个游标的方式有多种，可以显示定义CURSOR cursor_name is select * from table，也可以定义动态游标，游标关键词CURSOR
TYPE ref_cursor_type IS REF CURSOR; --定义一个动态游标
students ref_cursor_type; --定义班级集合为一个游标类型
student_row student%rowtype; --定义班级类型，类型为student表行类型
--存储过程开始
begin 
--把查询出来的class_name 赋值给输出变量className,查询条件为classId
select class_name into className from class where id = classId; --打开游标并赋值 open students for select * from student where fk_class =classId; --把查询结果赋值给输出变量，实际上可以直接open classStudents for select * from student where fk_class =classId; classStudents := students; --循环输出游标，循环有三种方式，for in循环，fetch循环，while循环 --fetch循环 loop fetch classStudents into student_row; --当循环到空跳出循环 EXIT WHEN classStudents%NOTFOUND; DBMS_OUTPUT.put_line('学生名：'||student_row.student_name); end loop; DBMS_OUTPUT.put_line('班级名：'||className); --存储过程结束 end findclass; 

into前面写table列名，后面写需要赋值的变量名，顺序要对
select student_name,class_name into studentName,className from class;

转载自https://www.jianshu.com/p/159f3f41f4cc