MySQL 高级 - 存储过程 - 语法 - 游标

游标/光标-- 查询emp表中数据, 并逐行获取进行展示create procedure pro_test11()begindeclare e_id int(11);declare e_name varchar(50);declare e_age int(11);declare e_salary int(11);declare emp_result cursor for select * from

小草dym

170人浏览 · 2021-03-12 22:01:59

小草dym · 2021-03-12 22:01:59 发布

游标/光标

-- 查询emp表中数据, 并逐行获取进行展示
create procedure pro_test11()
begin
  declare e_id int(11);
  declare e_name varchar(50);
  declare e_age int(11);
  declare e_salary int(11);
  declare emp_result cursor for select * from emp;
  
  open emp_result;
  
  fetch emp_result into e_id,e_name,e_age,e_salary;
  select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
  
  fetch emp_result into e_id,e_name,e_age,e_salary;
  select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
  
  fetch emp_result into e_id,e_name,e_age,e_salary;
  select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
  
  fetch emp_result into e_id,e_name,e_age,e_salary;
  select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
  
  fetch emp_result into e_id,e_name,e_age,e_salary;
  select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
  
  close emp_result;

end$

通过循环结构 , 获取游标中的数据 :

create procedure pro_test12()
begin

  declare e_id int(11);
  declare e_name varchar(50);
  declare e_age int(11);
  declare e_salary int(11);

  declare has_data int default 1;
  
  declare emp_result cursor for select * from emp;

  DECLARE EXIT HANDLER FOR NOT FOUND set has_data=0;
  
  open emp_result;
  
  repeat
    fetch emp_result into e_id,e_name,e_age,e_salary;
    select concat('id=',e_id , ', name=',e_name, ', age=', e_age, ', 薪资为: ',e_salary);
    until has_data = 0
  end repeat;
  
  close emp_result;

end$