Saving / loading user built query using custom query builder

We're building a c# web application that will have a part that allows end users (the admins of the application) to create sql queries that will later be used to validate data. The way they'll create the queries is they'll have buttons for the operators and other UI elements for creating the query.

Basically what I'm wondering is the best way to save the queries for later use & also reloading the query into the editor for editing, so whether it be saving it as a stored procedure or as xml to save save in a table or something else?

Thanks