Crystal Reports -将变量查询下推到服务器

Question

在使用Crystal Reports时，我遇到了将查询下推到SQL服务器的问题(我目前正在使用Crystal Reports 2013)。

如果我输入以下内容作为记录选择公式，Crystal将使用WHERE子句来选择记录：

{LINKAGE.ENTITY_ID_1} = 1 and
{LINKAGE.ENTITY_TABLE_1} = "ENT" and
{LINKAGE.ENTITY_TABLE_2} in ["DOC","PHO"]

-给予-

SELECT "LINKAGE"."ENTITY_ID_1", "LINKAGE"."ENTITY_TABLE_1", "LINKAGE"."ENTITY_TABLE_2"
FROM   "TESTING_DB"."dbo"."LINKAGE" "LINKAGE"
WHERE  "LINKAGE"."ENTITY_ID_1"=1 AND "LINKAGE"."ENTITY_TABLE_1"='ENT' AND ("LINKAGE"."ENTITY_TABLE_2"='DOC' OR "LINKAGE"."ENTITY_TABLE_2"='PHO')

如果我将‘硬编码’值改为使用变量，Crystal在选择记录时不再包含WHERE子句：

numbervar valueNumber := 1;
stringvar valueString := "ENT";
stringvar array valueArray := ["DOC","PHO"];

{LINKAGE.ENTITY_ID_1} = valueNumber and
{LINKAGE.ENTITY_TABLE_1} = valueString and
{LINKAGE.ENTITY_TABLE_2} in valueArray

-给予-

SELECT "LINKAGE"."ENTITY_ID_1", "LINKAGE"."ENTITY_TABLE_1", "LINKAGE"."ENTITY_TABLE_2"
FROM   "TESTING_DB"."dbo"."LINKAGE" "LINKAGE"

从文档上看，这听起来不应该有什么问题，所以我不太确定我可能遗漏了什么。任何有见地的人都会非常感谢！

Answer 1

我似乎已经在Crystal Reports用户指南中找到了答案。这里提到只有常量或参数值可以下推，而不能下推变量：

https://help.sap.com/doc/dfc124becfa845ffa91b1e717b20e3ec/2016%20SP3/en-US/4770d0cd6e041014910aba7db0e91070.html#loio4770d0cd6e041014910aba7db0e91070