Using a query parameter to populate controls on multiple pages, and apply to multiple sources

[KeySmasherGuy]

Hi,

I am attempting to make a parameter, say country, that applies to multiple data sources. Ideally, I can set this parameter by encoding it in the URL, and have all my sources filter on that single parameter. From the docs, it appears that a parameter has to be linked to a data source. Is this accurate? Would this imply that I would have to create a parameter for each source (with the same data for each parameter), and encode its respective URL parameter name in the URL? Is there a potential way to have one parameter, that is re-used across all my data sources?

Furthermore, what would be the best way to use this parameter to filter the datasources? Is the recommended approach to use the parameter in the custom SQL query in the data source and just apply the filter there? (as mentioned here)

Any feedback would be greatly appreciated. Please let me know if any further information is required.