What is a Data Lookup Rule in ServiceNow?

[Mummadisetty]

I would like to understand the concept of Data Lookup Rules in ServiceNow with a practical example.

How are they configured, and how do they automatically set field values on a form?

Additionally, what are best practices for using them in production environments.

[GlideFather]

Hi @Mummadisetty,

the easiest example to understand is calculation of Priority. That field is read-only and changes as per the values in Impact and Urgency.

Urgency 1 + Impact 1 = Priority 1,

Urgency 2 + Impact 2 = Priority 2,

etc...

https://yourinstance.service-now.com/dl_u_priority_list.do

You can check it in the lookup definitions

https://yourinstance.service-now.com/dl_definition_list.do

[Dr Atul G- LNG]

Hi @Mummadisetty 

https://youtu.be/K7L3n3AUYmE

My video will be helpful

https://www.servicenow.com/docs/r/washingtondc/application-development/table-administration-and-data...

[yashkamde]

Hello @Mummadisetty ,

Data Lookup Rules are a no‑code automation feature in ServiceNow that allow administrators to automatically set field values on a form based on defined conditions. They’re essentially a way to replace small client scripts or business rules with a simpler, maintainable configuration.

For Ex : In Incident table Priority matrix i.e how on the basis of impact x Urgency Priority is set..
Below I implemented this in custom table :

For this you have to make a record in Data look definition (Navigate through application navigator) :

Also Matcher table should be custom which is extended by Data lookup matcher rules table and set the choices their :

If my response helped mark as helpful and accept the solution.