1) You can obtain a reference to the AFTable via AFDatabase.Tables Property . From there, you can use the AFTable.Table Property to get the data as a .NET DataTable object, from which you can query the table.
2) One recommendation is to use parameters in a linked table query. See the section "Using parameters in a linked table query" in the PI System Explorer guide for how to configure the AFTable for this support. This can help reduce the number of rows returned to the client.
Thanks for the response Barry. I will attempt access to the linked table through the AFTable.Table property and report back here.