The creative asset field is a link to your image ad url within our Digital Display and Video OneView. This field is specific to the Google Ads Ad Performance and Google Ads Ad Performance Conversion datasets, and it is defined as the prefix value with "https://tpc.googlesyndication.com/pageadimg/imgad?id=" to get the full URL. For example, if your ad image is given the id of 123456789, the field will read:
Within your dashboard, we define this value as “Creative Asset”, and clicking “View Link” will allow you to view the asset if it is available.
If this field is not available for a particular data source, it is labeled “Not Available”.