将 IN 子句与存储过程一起使用时,Firebird 查询花费的时间太长

Firebird query taking too long when using IN clause with Stored Procedure

为了一份报告,我不得不编写一个递归存储过程GET_RECIPE_STEPS_ID(recipe_id)。它 returns 属于食谱类型的步骤 ID。即

SELECT GET_RECIPE_STEPS_ID.ID FROM GET_RECIPE_STEPS_ID(3189)

It Returns
3189
3190
3191
3192

当我 运行 它自己运行时它很快(比如 0.031 秒的执行时间)。但如果它要在查询中与 IN 子句一起使用,则需要很长时间。像下面的查询差不多用了12分钟。

SELECT rs.RECIPEID
FROM RECIPESTEPS rs
WHERE rs.RECIPEID IN (select GET_RECIPE_STEPS_ID.ID from GET_RECIPE_STEPS_ID(3189))

这相当于以下查询,几乎与存储过程本身一样快(0.038 秒)

Select rs.RECIPEID
FROM RECIPESTEPS rs
WHERE rs.RECIPEID IN (3189, 3190, 3191, 3192)

存储过程

CREATE OR ALTER PROCEDURE GET_RECIPE_STEPS_ID 
 (recipe_id integer) 
RETURNS 
 (id integer)
AS 
declare variable coType integer;
BEGIN
  /* Recursive Procedure 
   * For Passed Recipe 'Recipe_id', it Returns the step's which are of type Recipe again.
   * 
   * If any step is of type Recipe(i.e COTYPE = 1)
   * Then it calls itself again for that step(Recipe) 
   */
    id =: recipe_id;
    SUSPEND;

    FOR SELECT rs.COMMODITYID, c.COTYPE
        FROM RECIPESTEPS rs 
        LEFT JOIN COMMODITIES c ON c.COMMODITYID = rs.COMMODITYID
        WHERE rs.RECIPEID  =: recipe_id INTO :id, :coType
    Do
    BEGIN
        IF(coType = 1)
        THEN 
            FOR SELECT r.RECIPEID FROM RECIPES r WHERE r.LATEST = 1 AND r.COMMODITYID =:id into :id
            DO
            BEGIN
                FOR SELECT GET_RECIPE_STEPS_ID.ID
                    FROM GET_RECIPE_STEPS_ID(:id) INTO :id
                DO
                BEGIN
                    SUSPEND;
                END
            END     
    END 
END^

问题有两个:

  1. IN 一开始并没有很好的表现
  2. 在这种情况下,存储过程会针对每一行执行,而不是像您期望的那样执行一次;我猜 Firebird 优化器不会推断此存储过程调用与查询不相关。

如果您将查询转换为使用 INNER JOIN 而不是 IN:

,它的性能可能会更好
select rs.RECIPEID
from GET_RECIPE_STEPS_ID(3189) grs
inner join RECIPESTEPS rs
  on rs.RECIPEID = grs.ID

我假设您的实际查询可能更复杂,否则 select ID from GET_RECIPE_STEPS_ID(3189) 就足够了。

上述查询的行为与IN略有不同,例如,如果ID在存储过程输出中多次出现,它现在也会产生多行。您可能需要相应地进行调整。