Returns the amount of rows in this typed list.

Gets / sets ObeyWeakRelations, which is the flag to signal the collection what kind of join statements to generate in the query statement. Weak relationships are relationships which are optional, for example a customer with no orders is possible, because the relationship between customer and order is based on a field in order. When this property is set to true (default: false), weak relationships will result in LEFT JOIN statements. When set to false (which is the default), INNER JOIN statements are used.