The subject disclosure pertains to systems and methods that facilitate retrieval of data. In particular, an application defined data shape can regulate loading of data for use in an object relational mapping system, enabling the object-oriented application to access data in a relational data base system. Data shapes define policies that control data retrieval, enabling efficient data loading. A data shape allows users to declaratively specify a set of policies to be applied to all queries associated with the data shape. In particular, data shapes can include policies that control eager loading. In addition, data shapes can also include filtering policies intended to reduce or limit data retrieved from a relational database