Get Table information from dataset Programmatically

Sorry for the confusion lbendlin .
My need is to programatically find the list of source tables which are backing a given powerbi report.

That's what I gave you with the DMV query.  You need to take that M code and parse it. It contains the server, database and query.

lbendlin , I am afraid I am getting different results for that query:

These are not the tables present in our Source. Am I missing something? 

Most likely you connected to the wrong endpoint. Different dataset maybe?

I verified that I am looking at right dataset. However, PowerBI report is built using "import" and not "direct query".
Does it make a difference lbendlin ?

No, once you access the dataset it doesn't matter much if  the query connection type is import/ direct query or mixed.  

I just tried it with one of my direct query datasets and got the expected result. 

As expected it will not work at all with live connections.

I had the same problem as pgelli when using lbendlin 's suggestion of SELECT * FROM $SYSTEM.TMSCHEMA_PARTITIONS; I was receiving the DAX QueryDefinitions and not the M Query defintions (super useful, just not what I needed).  What solved it for me was instead using  SELECT * FROM $System.DISCOVER_M_expressions.  Hopefully this saves someone else some time for this use case.