Hi Urva,

An HTML+ portlet is just HTML+JS+CSS - so this is "standard" web development.

Regarding retriving the data, there are two ways to do it:

- If total amount of data is not too much, you can retrieve all the details upfront in the main datasource, and aggregate it as needed before showing it in the grid. When a value in the grid is clicked, you already have all the detailed data and can show it in any way you want.

- If total amount of data is too large, have the main datasource retrieve pre-aggregated data to show in the grird, and when a value in the grid is clicked, make a call to an additional datasource that will retrieve detailed values along with the clicked value as a filter - make sure to show some "loading" indicator while doing this as this call may take some time depending on the complexity of the query.

In both case, there is no need to create multiple HTML+ portlet and do some "drill down" between them. Just create a single HTML+ portlet that will drill down into the data and modify its contents (with JS) when drilling down/up the data.