Question

我有一个具有以下结构的表：

路径： OBJECTID 步时间戳

例如

objectId    step    timestamp
 1          IN     2014-04-12
 1          OUT    2014-04-13
 3          OUT    2014-04-11
 3          PLACED 2014-04-10

我需要进行查询，产生以下结果：

ObjectId      steps
 1            IN,OUT
 3            PLACED,OUT

我尝试了递归，如下所示：

WITH TEMP(objectId,STEP,RN) AS
(
(   

SELECT * FROM ( 
    SELECT  SCE.objectId
    ,SCE.STEP
    ,ROW_NUMBER() OVER (  PARTITION BY  objectId order by timestamp ) as RN

    FROM KAP.path SCE 
    WHERE   SCE.STEP IN ('IN','PLACED','OUT')
) WHERE RN =1

)
UNION ALL 
(

SELECT * FROM (     
    SELECT SCE1.objectId
    , STEP
    , ROW_NUMBER() OVER (  PARTITION BY  objectId order by timestamp ) as   RN1

    FROM TEMP ,  path SCE1
    WHERE TEMP.objectId = SCE1.objectId
    AND  SCE.STEP IN ('IN','PLACED','OUT')

)WHERE RN +1 = RN1

) 
) select * from TEMP ORDER BY 1;

但由于

，此查询失败

全面选择递归公用表表达式＆＃34; DB2INST.TEMP＆＃34;必须是两个或更多全选的UNION而不能包括列函数，GROUP BY子句，HAVING子句，ORDER BY 子句，或包含ON子句的显式连接

请问您能告诉我，我如何修复我的查询以提供所需的输出或任何其他想法更有效？

DB2中的递归SQL

0 个答案: