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HomeDatabaseMysql TutorialOracle type/rowtype/record

RECORD: 记录类型,可以理解为是几列数据的集合,使用的时候注意结果集只能有一行 ,引用时使用.来引用内部元素 declare type v_my_record is record (v_ename emp.ename%type, v_job emp.job%type); v_dname dept.dname%type; v_my v_my_record; --需要先定

RECORD: 记录类型,可以理解为是几列数据的集合,使用的时候注意结果集只能有一行

,引用时使用.来引用内部元素

declare type v_my_record is record

        (v_ename emp.ename%type, 
         v_job   emp.job%type);
v_dname dept.dname%type;
v_my v_my_record;   --需要先定义type  再声明变量
begin
v_dname:=&dname;
select ename,job into v_my
from emp inner join dept 
on emp.deptno=dept.deptno 
where upper(dept.dname)=upper(v_dname) and rownum=1;
dbms_output.put_line(v_my.v_ename||' '||v_my.v_job);
exception when no_data_found then
dbms_output.put_line('nononono..');

end;

ROWTYPE:可以理解为是几列数据的集合,可以对表、视图使用,应用的时候使用 "." 和record类似:

create or replace view v_emp 
as 
select ename,dname,empno 
from emp,dept 
where emp.deptno=dept.deptno;

--使用视图%rowtype
declare 
v_row v_emp%rowtype;
v_empno emp.empno%type;
begin
v_empno := &请输入编号;
select * into v_row from v_emp where empno= v_empno;
dbms_output.put_line(v_row.ename||','||v_row.dname);
end;


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