After you have accessed your data on DoubleClick, you will have to transform it based on two main factors,
- The limitations of the database that is going to be used for loading
- The type of analysis that you plan to perform
Each system has specific limitations on the data types and data structures that it supports. If you want to push data into Google BigQuery, you can send nested data like JSON directly, but keep in mind that in the case of a SOAP API like DoubleClick, you get XML responses.
Of course, when dealing with tabular data stores, like Microsoft SQL Server, this is not an option. Instead, you will have to flatten out any data you own, just as in the case of JSON, before loading into the database.
Also, you have to choose the right data types. Again, depending on the system you will send the data to and data types that the API exposes to you, you will have to make the right choices. These choices are important because they can limit the expressivity of your queries and limit your analysts on what they can do directly out of the database.
With DoubleClick data, you have two main additional sources of complexity. When it comes to data types, you have to keep in mind that SOAP uses XML to describe the service and data, so data types that you have to map are coming from XML and might have automatically been transformed into the primitive data types of the language that you are using.
Also, you have to consider that the reports you’ll get from DoubleClick are like CSV files in terms of their structure, and you need to identify somehow what and how to map to a table into your database. This way, you will be able to combine and query your own data to assess the performance of various ads and finally improve ROI for display ad campaigns.