How can I calculate the size of a T-SQL query in bytes transfered across the network?
I know I can approximate it by examining data types of columns (varchars are an interesting twist though), but are there tools that'll give me the number of bytes (including and excluding TCP/IP headers) used up while transferring the query and its results to and from the SQL Server?
If you are using the Microsoft Sql Server Management Studio, you can toggle the "Include Client Statistics" from the "Query" menu.
You will get some network statistics like
You can also leave that option on and get an average of all query executions.