According your comment, please look at this Azure SQL database document: An overview of Azure SQL Database security capabilities:
This article outlines the basics of securing the data tier of an application using Azure SQL Database. The security strategy described follows the layered defense-in-depth approach as shown in the picture below, and moves from the outside in:

It will help you learn from the Azure SQL database security. To know more about the access control and Authorization.
Azure also gives the security best practices to teach you how to use these them.
Reference: Azure SQL Database security best practices playbook. This document provides guidance on how to solve common security requirements for new or existing applications using Azure SQL Database.
Hope this helps.