Porting to the new package involves namespace and package reference updates. More details can be found in porting-cheat-sheet.
In scope
Namespace changes, package reference updates, and everything mentioned in the porting cheat sheet linked above.
Out of scope
Functionality changes that need manual reviewing.
Risks / unknowns
An application may face database connectivity issues after migration due to insecure customer environment setups and enhanced security enabled by default by the new library. From security perspective, this is an acceptable risk and customers must be made aware of the functionality changes to help resolve connectivity issues.
Summary
Microsoft.Data.SqlClient is the successor of System.Data.SqlClient, actively supported by Microsoft, while System.Data.SqlClient is in security maintenance mode.
Motivation and goals
MDS made it's entry in 2019 and has gained stability and customer adoption over the years. The first introductory blog post is here: https://devblogs.microsoft.com/dotnet/introducing-the-new-microsoftdatasqlclient/
Porting to the new package involves namespace and package reference updates. More details can be found in porting-cheat-sheet.
In scope
Namespace changes, package reference updates, and everything mentioned in the porting cheat sheet linked above.
Out of scope
Functionality changes that need manual reviewing.
Risks / unknowns