MySQL递归存储过程...已达到限制0...无法更改max_sp_recursion_depth变量。

Question

更新：好的，我已经调试了这个问题，并发现通过执行 select @@max_sp_recursion_depth，我可以看到变量设置为15，然而，当我用CALL single_limb_portfolio_list(xaccount_id, xparent_portfolio_id); 回调到它自己时，我收到了错误提示递归限制0已被达到，但它从未迭代过一次。

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运行下面的递归存储过程时，我不断收到“递归限制0已被超过”的错误提示，即使我将其设置为 SET max_sp_recursion_depth = 15 ; 我是不是在错误的地方设置了这个变量？它的行为就像从未被设置过一样，总是保持为零？

提前感谢您的帮助。

递归存储过程如下：

CREATE DEFINER=`aaron`@`localhost` PROCEDURE `single_limb_portfolio_list`(xaccount_id INT, IN portf_id_in INT, OUT str_portf_list VARCHAR(455))
BEGIN
    DECLARE xportfolio_ID INT DEFAULT NULL ;
    DECLARE xp_name INT DEFAULT NULL ;
    DECLARE xparent_portfolio_id INT DEFAULT NULL ;
    DECLARE xstr_list VARCHAR(455) ;

  SET max_sp_recursion_depth = 15 ;

    SELECT portfolio_id, p_name, parent_portfolio_id
    FROM portfolio
    WHERE account_id = xaccount_id
    AND archived = 0
    AND portfolio_id = portf_id_in
    INTO xportfolio_ID, xp_name, xparent_portfolio_id;

   IF xportfolio_ID IS NULL /* We have reached the top of the tree and there are no more parents for the portfolio list */
    THEN
    SET str_portf_list = xstr_list; #Set the full tree list to the variable that will be inserted as a row into the temp table previously created
   ELSE
    CALL single_limb_portfolio_list(xaccount_id, xparent_portfolio_id); #call the sproc with the next portfolio id to get the next parent id
    SET xstr_list = concat(xp_name,"->",xstr_list);   #Add the portfolio name to the overall portfolio list. Output like: "California -> Los Angelas"
   END IF;

END

- Ronedog

Answer 1

这里有一个非递归的解决方案，你可以根据你的模型进行调整（http://pastie.org/1259300）

drop table if exists product;

create table product
(
prod_id smallint unsigned not null auto_increment primary key,
name varchar(255) not null,
parent_id smallint unsigned null,
key (parent_id)
)engine = innodb;


insert into product (name, parent_id) values
('Products',null), 
   ('Systems & Bundles',1), 
   ('Components',1), 
      ('Processors',3), 
      ('Motherboards',3), 
        ('AMD',5), 
        ('Intel',5), 
           ('Intel LGA1366',7);


delimiter ;

drop procedure if exists product_hier;

delimiter #

create procedure product_hier
(
in p_prod_id smallint unsigned
)
begin

declare v_done tinyint unsigned default 0;
declare v_depth smallint unsigned default 0;

create temporary table hier(
 parent_id smallint unsigned, 
 prod_id smallint unsigned, 
 depth smallint unsigned default 0
)engine = memory;

insert into hier select parent_id, prod_id, v_depth from product where prod_id = p_prod_id;

/* http://dev.mysql.com/doc/refman/5.0/en/temporary-table-problems.html */

create temporary table tmp engine=memory select * from hier;

while not v_done do

    if exists( select 1 from product p inner join hier on p.parent_id = hier.prod_id and hier.depth = v_depth) then

        insert into hier 
            select p.parent_id, p.prod_id,  v_depth + 1 from product p 
            inner join tmp on p.parent_id = tmp.prod_id and tmp.depth = v_depth;

        set v_depth = v_depth + 1;          

        truncate table tmp;
        insert into tmp select * from hier where depth = v_depth;

    else
        set v_done = 1;
    end if;

end while;

select 
 p.prod_id,
 p.name as prod_name,
 b.prod_id as parent_prod_id,
 b.name as parent_prod_name,
 hier.depth
from 
 hier
inner join product p on hier.prod_id = p.prod_id
inner join product b on hier.parent_id = b.prod_id
order by
 hier.depth, hier.prod_id;

drop temporary table if exists hier;
drop temporary table if exists tmp;

end #

delimiter ;


call product_hier(3);

call product_hier(5);

- Jon Black

---

我会给你点头的...谢谢回复。我做了类似的事情，但不是在存储过程中。我已经有一个我编写的用于遍历树并给我想要的结果的PHP函数，然后我意识到我可以简单地运行该函数，然后将所需的树结构插入到表中。 - Ronedog