Decide how to move forward deprecating compatibility mode for Saga lookup

[kentdr]

Background

NServiceBus.Persistence.AzureStorage Version 1 and 2 used a SecondaryIndex entity to find the saga. The secondary index entry used a partition key Index_{sagaDataTypeName}_{correlationProperty.Name}_{Serialize(correlationProperty.Value)}and a RowKey with string.Empty.

https://github.com/Particular/NServiceBus.Persistence.AzureTable/blob/b0a558882ca8004c264fa88ee3380f7ae78a9dcb/src/NServiceBus.Persistence.AzureStorage/SagaPersisters/SecondaryIndices/SecondaryIndexKeyBuilder.cs#L13C47-L13C146

The secondary index algorithm did attempt to load things by the well know partition and row key or in the worst case tried to fall back to a full table scan based on the Saga ID.

NServiceBus.Persistence.AzureTable version 3 was built to be by default fully compatible with NServiceBus.Persistence.AzureStorage Version 1 and 2

It supports both sagas that use secondary index entries as well as sagas that don't have a secondary index entries. By default the persister operates in the compatibility mode but doesn't fall back to full table scans. If compatibility with sagas stored with Version 1 of the persister is required full table scan has to be enabled.

https://docs.particular.net/persistence/upgrades/asp-2to3#compatibility

The table scanning was made opt-in because it is a very expensive operation that can create huge costs on larger tables.

NServiceBus.Persistence.AzureTable version 4 disabled the compatibility mode by default

This package continues to be fully compatible with the NServiceBus.Persistence.AzureStorage version 1 and 2. It supports both sagas that use secondary index entries as well as sagas that don't have a secondary index entries. It's important to note that the compatibility mode does need to be manually enabled. It has been disabled by default in favor of performance.

https://docs.particular.net/persistence/upgrades/asp-4to5#switching-to-azure-data-tables-compatibility-mode