How to query all add/delete tables in SDE and have a count of each as a row in the output

You probably want to use an alias, like

SELECT COUNT(*) AS totalRecords FROM <tablename>

and then expose totalRecords.

Not sure about the union part, I think I would send one feature for each query, with the tableName as an attribute so you get something like

SELECT COUNT(*) AS totalRecords FROM @Value(tableName)

This way you will get a feature for each table with tableName and totalRecords, which can be directly written to excel.

Hmm, tried that and it’s a successful query, but the output is blank. 

I suspect the result is there but unexposed. If you select the record in the visual preview or in the Data Inspector, activate the Feature Information window and select the record. Then you will see everything about the feature on the right side of the screen.

Ah yes, I do see that its not exposed, but the property & data type columns are blank, but the value is correct. 

Can you printscreen what you see?

If you click on the arrow with unexposed attributes, you should be able to see the unexposed attribute names.

That worked! Thank you so much!

Cheers!