RE: I am running a GL report and wanted to know if I could add a “external id” as a column
You can add “external id” and other custom fields as many you required. This can be done by NetSuite Customization. Drop your requirement here to connect on a quick call with you: https://www.streamssolutions.com/contact-us/
We may support you regarding all your NetSuite Queries, Integration, and Customization.