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Adam Machanic has made a user feedback item, you can cast your vote to urge Microsoft to make it available.
It has been picked up by Microsoft, and has been under review since april 6 2018.
You could get your
DTU count or
CPU count, depending on your model from a certain reporting interval from the
SELECT dtu_limit ,MAX(end_time) as end_time
GROUP BY dtu_limit; -- DTU Model
SELECT cpu_limit ,MAX(end_time) as end_time
GROUP BY cpu_limit; -- VCpu Model
The maximum of 5 Dtu's on my basic tiered database is returned by the query
5 2019-03-21 19:17:05.237
And as a result of being on the DTU model, VCpu count will return
NULL 2019-03-21 19:17:05.237