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Plsql 循环帮助的光标?不明白_Plsql - Fatal编程技术网

Plsql 循环帮助的光标?不明白

Plsql 循环帮助的光标?不明白,plsql,Plsql,我不明白employeeRec来自哪里?这是否类似于java中的Advanced for循环,其中employeeRec充当通过employeeCur的循环项 employeeRec称为循环索引,并隐式声明为%ROWTYPE记录变量,该变量与游标的类型匹配employeeCur 如果不是循环的游标,则首先声明游标,然后声明游标变量,打开游标,获取,注意何时退出循环,关闭游标,例如 declare cursor employeeCur is select empid, ...;

我不明白employeeRec来自哪里?这是否类似于java中的Advanced for循环,其中employeeRec充当通过employeeCur的循环项


employeeRec
称为循环索引,并隐式声明为%ROWTYPE记录变量,该变量与游标的类型匹配
employeeCur

如果不是循环的游标,则首先声明游标,然后声明游标变量,打开游标,获取,注意何时退出循环,关闭游标,例如

declare
  cursor employeeCur is 
    select empid, ...;
  employeeRec employeeCur%rowtype;          --> this
begin
  open employeeCur;
  loop
    fetch employeeCur into employeeRec;     --> this
    exit when employeeCur%notfound;
    update employee set ...
  end loop;
  close employeeCur;
end;
正如您所见,游标FOR循环更易于编写和维护,因为Oracle为您执行了许多任务。

请阅读并接受答案