错误代码：1241。Workbench、MySQL，无法解析参数

Question

我正在使用 Workbench 来编写查询。以下过程已成功创建（没有问题）。但是在尝试执行该功能时出现此错误： 错误代码：1241。操作数应包含 1 列
如果有人帮助我，我将不胜感激。

delimiter $$
create procedure usp_raise_salaries1(department_name varchar(30))
begin

update employees as e
set salary = salary * 1.05
where (select first_name, salary from employees as e 
join departments as d on e.department_id = d.department_id
where d.name = department_name);


end $$

delimiter ;

set @answer = 'Sales';
call usp_raise_salaries(@answer); -- The Workbench gives error at this line.

Answer 1

您从子查询中得到很多行，因此您需要 'IN 子句来 select 要更新的行

delimiter $$
create procedure usp_raise_salaries1(department_name varchar(30))
begin

update employees as e
set salary = salary * 1.05
where (first_name, salary) IN (select first_name, salary from employees as e 
join departments as d on e.department_id = d.department_id
where d.name = department_name);


end $$

delimiter ;

错误代码：1241。Workbench、MySQL，无法解析参数

Error Code: 1241. Workbench, MySQL, cannot resolve the parameters

mysql

error-handling

procedure

workbench

operands