Entra ID Managed Identity versus SQL Login Password Expiration for Least-Privilege Azure SQL Access

In Azure SQL Database, least-privilege access is enforced through contained database users and database roles for both authentication methods. The design choice between token-based and password-based credential management affects how expiration events impact connection validity under pooled client usage.

Microsoft Entra ID managed identities depend on short-lived OAuth tokens whose lifetimes and refresh cadence are governed by the Microsoft Entra identity platform and client library cache behavior, not by Azure SQL Database directly. SQL logins with CHECK_EXPIRATION enabled can reject connections once a password exceeds its defined expiration interval, but the consistency of failure timing across connection pool recycle cycles is not explicitly documented.

• How does pooled connection recycle interact with Entra ID token cache expiration versus SQL login password expiration in terms of immediate versus delayed authentication failure?
• Does CHECK_EXPIRATION behavior in Azure SQL Database align with on-premises SQL Server password policy timing, and at what point does a pooled connection attempt fail after password expiration?
• For an organization balancing least-privilege enforcement with operational rotation overhead, what are the trade-offs between managing identity platform token lifetimes and maintaining SQL login password expiration policies?