mysql

leetcode题目：

 

1)

CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
BEGIN
  RETURN (
      # Write your MySQL query statement below.

  select distinct Salary from Employee e where N = (select count(distinct Salary) from Employee where Salary >= e.Salary )

  );
END

create function 及其调用
delimiter//
create function querytmp()
returns int
begin
declare ecount int;
select count(*) into ecount from emp;
return (ecount);
end//
 
select querytmp()//
 
‘procedure及其调用
delimiter//
CREATE  PROCEDURE proctmp(in param1 int,out param2 varchar(30))
begin
select name into param2 from emp where id=param1;
end 
DELIMITER ;
 
call proctmp(3,@a);
select @a;