Symptoms
Assume that you use Microsoft SQL Server 2019 or 2017. When you use the .NET Framework DbDataAdapter.FillSchema method to return table schema on the database that has a compatibility level of 140, you notice that the method returns a NULL value. However, when the method is used on a database that has compatibility level of less than 140, it returns the correct values.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Resolution
This issue is fixed in the following cumulative updates for SQL Server:
About cumulative updates for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
References
Learn about the terminology that Microsoft uses to describe software updates.