For the definition of data stream, it is essentially a PI Tag. However, it is a unique PI tag so that the same tag on multiple views will only count as one. If you delete a view, then the unique data stream from that view can be recovered in 7 days.
Your fixed values or table lookups won't count as a unique data stream. Only PI Point Data references are counted.
Some related discussion is contained in below whitepaper on PI Integrator. In general, we recommend you to focus your area of exploration using BI Tools or projects. PI Integrator cannot function as a 1:1 replication tool. Please take a look at the whitepaper.
Also, a brief data stream is described as below: