My preferred method would be as follows:

• Use a FeatureReader in "Schema Only"-mode to get a list of all the table names.
• Use a SQLExecutor to retrieve the number of records for each table, e.g.

select count(1) as MY_TABLE_COUNT
from @Value(fme_feature_type_name)

• Use a Tester to check if MY_TABLE_COUNT= 0

 This will avoid reading any data into FME, which is very efficient especially if there are tables with a lot of data among the empty ones.

You'll find it on the schema feature, it's not necessary to expose it manually (note that the name is lower case):

Make sure to configure the FeatureReader to only read the schema features, and not to include the table contents:

Thanks a lot