Azure SQL DB will be charged per hour or per seconds based on your configuration.
From the portal, open SQL DB > Configure tab and see the configuration. It should the cost per Month.
So cost is not per query here. Check Pricing calculator and pricing page for Azure SQL here -
https://azure.microsoft.com/en-us/pricing/details/sql-database/single/
----------
Please don't forget to Accept Answer and Up-vote if the response helped -- Vaibhav