Q:

I want to provide an option for applying filters at runtime on the selected columns in my query generated from the active query builder. 
For example: I have a select query on table but I want to give user the facility to select a date range or threshold value based on which data should be retrieved. I want to provide that option visually to the user. Is there any mechanism we can do so.

A:

We've made the special control to let users easily define filters to queries which are already built. It is called the CriteriaBuilder. It is a user interface to the QueryTransformer component which can also perform grouping, totals calculation and row limitation (paging). It is described here:
How to change sorting, add filters, limits and aggregations to the query?

The sample of the CriteriaBuilder usage is provided in the Full-featured demo if you are evaluating the WinForms or WPF or in the Query Results demo in the ASP.NET Edition.