​@Ayush kumar I would turn to the ONE Desktop app here and build a component rule. Using the Lookup step, you can not only check that the given value matches one of the values in the lookup file, but also capture the specific lookup key value that was found in the file. That is not something you can do in the web app.

In the Lookup step configuration, use the lookup.key expression to store the value into some working column:

From there you could calculate the difference between the src_value and the working column, and decide the VALID/INVALID result based on the outcome.

Does that help?

Thanks for the solution ​@Lisa Kovalskaia. That's quite helpful, just wanted to know how can I make this solution possible, I mean I am having my lookup and catalog item in web version, how can I establish a connection in between web version and desktop version and take my lookup and CI there , it would be great if you can provide any link of ataccama support/help document or link of any related community post.

​@Ayush kumar sure, first off, please connect your ONE Desktop to your ONE Platform:

With that integration, you can access and work with many key assets of the Web app, here's more on that:

For your specific use case, you’ll want to build a DQ rule that relies on a validation component:

https://docs.ataccama.com/one/15.4.0/data-quality/validation-components.html#working-with-validation-components

Note that you will need to download the lookup file you have in your ONE Web app and upload it to the component in ONE Desktop - once you publish the component the lookup file will be uploaded and stored in Ataccama's object storage. Please refer to ONE Desktop Tutorials available within the app for additional info and examples.

When the component rule is ready, you can go back to your ONE Web app and apply the rule to a catalog item - just like you would apply any other rule built in the Web app. 

I would also encourage you to check out the Ataccama Academy, there's a wealth of resources for self-paced learning, could serve as a great reference for all things Ataccama.

If you have additional questions, let me know!

​@Lisa Kovalskaia your replies are helping me immensely would be following this method, just wanted to know if we have an automated process to - download the lookup file i have in my ONE Web app and upload it to the component in ONE Desktop because this lookup file is updated daily following a schedule and it will be quite challenging for me to update this lookup file everyday for various rules.