1.标量：
ag1：
declare
v_ename emp.ename%type;--自己称为单变量
begin
select ename into v_ename from emp where empno=&no;
dbms_output.put_line('雇员名称'||v_ename);
end;
ag2:
declare
type test1 is record(t1 emp.ename%type,t2 emp.sal%type);--定义记录型变量
v_tt test1;--v_tt为复合型变量test1
begin
select ename,sal into v_tt from emp where empno=&no;
dbms_output.put_line('雇员姓名'||v_tt.t1||' 薪资'||v_tt.t2);
end;
ag3:
declare
type test2 is table of emp.ename%type index by binary_integer;--PL/SQL 表类型
v_ename test2;
begin
select ename into v_ename(0) from emp where empno=7788;
dbms_output.put_line('雇员姓名：'||v_ename(0));
end;