用户通过subtype定义子类操作实例源码:
-- Created on 2018/3/21 by E.WANG
/*
使用subtype用定义子类型
*/
declare
subtype userName is char(20);
subtype sex is char(6);
uName userName;
userSex sex;
begin
uName := 'ewang ';
userSex := 'male';
dbms_output.put_line('user name:' || uName || 'Sex: ' || userSex);
end;
窗口截图:
运行结果截图: