What version FME do you use, and what is the format you use in the import?

In this case i was using
FME(R) 2023.2.0.0 (20231201 - Build 23764 - WIN64)

I was reading SQL Server Spatial with the JDBC driver

I’m not sure if this is expected behaviour or not. I think, using database formats, it might request the first 1.000 or 10.000 records to do this, but I’m not sure. I do not have access to a SQL server at the moment so I can’t try and reproduce.

I think I would submit a ticket to get an answer from a Safer. https://support.safe.com/hc/en-us/p/Support

Oh yeah maybe it is not checking all values. I have about 200 000 records in the database which is pretty standard in my type of work. 
I tried again but instead of reading the values import from a dataset i used import from feature cache where I had all the 199 856 objekts cached, but the result was the same. So maybe there is a limit to how many objects it is reading from the cache too.

I do recall reading something when this functionality first came out (the autofill in transformers) and I’m sure it mentioned it only looked through X number of features in the cache.

Now that was a few years ago, so that might’ve changed in newer versions