将 SQL 语句转换为 mySQL 存储过程

Question

我有一段 SQL 可以计算出高尔夫球手在排行榜上的排名。我对 Spring 很陌生，我认为我无法使用 Spring JDBC 执行此操作，因此我认为我需要将其转换为 mySQL 存储过程。

谁能给我一些关于我需要转换什么的指示？简单地把 CREATE PROCEDURE 和参数列表放在这个周围是行不通的。

SET @rank = 1, @prev_val = NULL, @prev_rank = NULL;
SELECT rank FROM
(
 SELECT @rank := IF(@prev_val!=winnings,@prev_rank+1,@rank) AS rank
     , @prev_val := winnings AS winnings
     , @prev_rank := @rank AS prevRank
     , t.golferID
  FROM 
     (
        select g.golferID, sum(winnings) as winnings 
        from results r
        join resultDetails rd on r.resultID = rd.resultID
        join golfers g on rd.golferID = g.golferID
        where r.status = 'C' and r.compID = 1 
        group by golferID order by winnings desc
     ) AS t
) AS showRank WHERE golferID = 16

Answer 1

这会让你开始：

drop procedure if exists get_golfer_rank;

delimiter #

create procedure get_golfer_rank
(
p_golferID int unsigned
)
proc_main:begin

set @rank = 0;

select 
...
where golferID = p_golferID;

end proc_main #

delimiter ;


call get_golfer_rank(18);

Answer 2

您的锻炼很好 - f00 假设您只想通过给定参数调用每个高尔夫球手的排名 - 因此构造...

create procedure get_golfer_rank
(
p_golferID int unsigned
)

还有……

where golferID = p_golferID;

仅限于单个高尔夫球手。

Answer 3

感谢您的线索。我解决了。粗略地说是

drop procedure if exists getRank;

delimiter $$

create procedure getRank()
begin

    set @rank = 1; 
    set @prev_val = NULL;
    set @prev_rank = NULL;

    select rank from
    (
     select @rank := if(@prev_val!=winnings,@prev_rank+1,@rank) as rank
         , @prev_val := winnings as winnings
         , @prev_rank := @rank as prevrank
         , t.golferid
      from 
         (
            select g.golferid, sum(winnings) as winnings 
            from results r
            join resultdetails rd on r.resultid = rd.resultid
            join golfers g on rd.golferid = g.golferid
            where r.status = 'c' and r.compid = 1 
            group by golferid order by winnings desc
         ) as t
    ) as showrank where golferid = 16;

end; $$

delimiter ;