Retryable SQL Error
As indicate in post Azure SQL transient errors by Mattias Karlsson, the following SQL errors are safe to retry:
| Error | Error Number |
|---|---|
| SqlErrorInstanceDoesNotSupportEncryption | 20 |
| SqlErrorConnectedButLoginFailed | 64 |
| SqlErrorUnableToEstablishConnection | 233 |
| SqlErrorTransportLevelErrorReceivingResult | 10053 |
| SqlErrorTransportLevelErrorWhenSendingRequestToServer | 10054 |
| SqlErrorNetworkRelatedErrorDuringConnect | 10060 |
| SqlErrorDatabaseLimitReached | 10928 |
| SqlErrorResourceLimitReached | 10929 |
| SqlErrorServiceErrorEncountered | 40197 |
| SqlErrorServiceBusy | 40501 |
| SqlErrorServiceRequestProcessFail | 40540 |
| SqlErrorServiceExperiencingAProblem | 40545 |
| SqlErrorDatabaseUnavailable | 40613 |
| SqlErrorOperationInProgress | 40627 |
I am not quite sure if I want to retry SqlErrorConnectedButLoginFailed or SqlErrorInstanceDoesNotSupportEncryption as these errors sound determined to me. But I guess it is based on the context. For a complete list of error codes, refer to Microsoft documentation here. The Connectivity guidance is worth reading as well.