SQL Server Paging detail problem handling

The SQL Server table query in this program gets 16 data, when page=1, the executed SQL statement can find the results, and is also 10 data

When page=2, the second page of the data should be 6, but the execution of page=2 when the SQL statement, the results of the query is empty! What is this for?

Reasoning, the SQL statement seems to have no problem, the last little analysis, found the problem, query time N.rid as Netclassid however in the Where condition I am directly using the NETCLASSID as a condition, in fact this is not feasible, Because Netclassid is a temporary field name, the database does not look for this condition, it does not recognize the field belongs to which database field, can not be found, continue to use the original N.rid as the query criteria!

Error:

That's right:

SQL Server Paging detail problem handling