Engine Works
Under the hood of Alteryx: tips, tricks and how-tos.
I have gotten the question of how to count records in a stream. The simplistic answer is to use a summarize tool. That works in most situations, but the summarize tool doesn't output any records if no records come in. It does seem like a valid request to be able to get a 0 count of records, because you might want to put something on a report that says "N Unmatched Records" and sometimes N is 0 and you want to know about it. After being asked 1 more time, I decided to throw together a simple macro to do it. You can find it in Alteryx post v 5.0.
How does it work? Very simple.
The macro takes your input and then runs a summarize tool. It also has text input that supplies the count of 0. I union together the count from the summarize & the text tool and then take the 1st record. If the count is >0 than the summarize tool produces a record and that is the one that is output. If there are no records coming in, then the dummy record showing the 0 count from the text tool gets output. Either way the macro outputs a record, even if there were none in the input. Another good example of how powerful macros can be - even simple ones.
