I'm attempting to use the below JS stored procedure to bulk delete documents in Cosmos DB (Document DB) from Azure Portal / Data Explorer. It is working for non-blank partitionKey values however it is not when the value is = "".

The stored procedure asks for a mandatory partitionKey value (as expected) and while it accepts a blank field, it won't identify records correctly (returns "deleted": 0). The equivalent ad-hoc SELECT query identifies the record successfully.

https://github.com/Azure/azure-cosmosdb-js-server/blob/master/samples/stored-procedures/bulkDelete.js

I have tried specifying partitionKey into request options adding one of below, but to no avail:

partitionKey : ""
partitionKey : null
partitionKey : {}
partitionKey : undefined