Coding with Sitecore

Applying Sitecore caching is an essential task when you build your site, It help improve your site general performance and decrease response time significantly , Output HTML cache is one of the different types of cache that Sitecore offers, I almost apply it everywhere on site rendering components. However, If you are applying Conditional rendering on a component (Personalization) and you are setting different datasources based on some conditions, Applying Caching on that Component with " Vary by Data " option checked will not work as expected, At first i thought that Sitecore will resolve Component datasource by applying the Conditional rules before adding that to the " Cache Key",  That was not the case :( . It turned out that Sitecore uses the default datasource applied on the component to generate the Cache Key, So you will always see the " Default " version of the component on the page, And all of Conditional rules will be ignored. I'm usin