https://learn.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlcommand.beginexecutexmlreader?view=netframework-4.8.1&redirectedfrom=MSDN
SqlCommand.BeginExecuteXmlReader Method (System.Data.SqlClient) | Microsoft Learn
Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and returns results as an XmlReader...
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