Tuple selection works like a filter: it allows tuples that meet the selection condition to pass and disallows tuples that do not meet the condition. The operator is given some input relation, as well as a selection condition about tuples in the input relation. A selection condition is a truth statement about a tuple’s attribute values, such as AreaSize > 1000. For some tuples in Parcel, this statement will be true and for others it will be false. Tuple selection on the Parcel relation with this condition will result in a set of Parcel tuples for which the condition is true.