"It is possible for FETCH FIRST N PERCENT to create poorly performing query plans when the N supplied exceeds 50 percent. In these cases query execution can take an order of magnitude longer to execute than simply returning the full table. If performance is critical using an explicit row count for limiting is recommended."
I don’t understand how fetch first n percent functionality can be replaced with explicit row count limiting. There may be a way to do it in a client side but we can not be sure of its performance advantage
