Once you have imported your contact files, you can edit your contacts, or add custom contact fields to database.
SendinBlue allows you to add an unlimited number of custom contact fields, such as: address, birthday, number of orders, etc. When you create a new field, you can choose a content type (e.g. text, number or date). The content type is used to correctly format and utilize your information. For example, your contacts can easily be filtered to show only contacts who have placed more than X orders.
You can even create a 'Category' field type that uses predefined values. For example, the 'Gender' field could be defined with a value of 1 for men and a value of 2 for women. (This could allow your contacts to specify their gender in your subscription form via a checkbox.)
SendinBlue also enables you to create transaction fields. If you have an e-commerce business, you can setup a sales tracking script and automatically populate your transactional fields with data such as spend amount or order ID. This would allow you to setup calculated fields, which can process formulates based on existing fields. For example, you could calculate: 30-day order totals, average spend, number of orders, etc. These calculated fields are very useful for advanced segmentation and for developing marketing automation workflows.