DB2：不允许参数化：'fetch first< X>行只' [英] DB2: Won't allow parameterize: 'fetch first <X> rows only'

问题描述

尽管在 Oracle DB中，它允许通过添加查询来参数化查询可以获取的行数：

Although in Oracle DB its is allowed to parametrize the number of rows that the query can fetch by adding to the query:

select ...
from ...
where ...
and rownum <= @MaximumRecords

我不能在 DB2 中运行的acuivalent查询添加类似的条件：
允许添加： / p>

I can't add similar condition to acuivalent query running in DB2: It is allowed to add:

select ... 
from ...
where ...
fetch first 500 rows only

（其中有固定行数）
但不是：

(where there is fixed number of rows) but not:

select ... 
from ...   
where ...      
fetch first :1 rows only

（：1 == @MaximumRecords）

(:1 == @MaximumRecords)

有人知道解决方案/解决这个问题吗？

Is someone aware of a solution/work-around to this problem?

推荐答案

我想我发现解。我刚刚运行这个查询，并给出了一个默认值为@MaximnumRecords
的工具，并且DB2不允许执行：

仅提取0行 strong>在任何情况下 - 这是问题。

I think I found the solution. I just ran this query with a tool that gave a 0 default value to @MaximnumRecords and apperently DB2 doesn't allow to perform:
"fetch first 0 rows only" in any case - that was the problem.

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