Do not execute sub-report when it's hidden in SSRS

requirement:  combine seperated reports in one main report and display sub-reports based on parameter selection.

Keywords: SSRS subreport hidden SSRS隐藏subreport

Explaination: 最近遇到一个头大的问题， 如何在SSRS中让隐藏的subreport不执行， 而不仅仅是隐藏起来让用户看不到，进而提高报表的性能。因为单纯的隐藏只是Layout层面的行为，底层的报表仍然在加载的时候会执行。

网上搜寻了半天，GOOGLE一堆英文， 最终还是自己在卫生间里灵机一动，解决方法如下：

Solution:

step1: set expression for visibility property of sub-report 

step 2:

add execution flag for sub-report

step 3:

add execution flag parameter in sub-report dataset query.