1. A system for querying a database using a logical data model, the system comprising: a logical data model comprising data representing a plurality of entities, each of the plurality of entities having one or more properties, and mappings to a plurality of physical database tables, the mappings configured to map the plurality of entities to the plurality of physical database tables in a physical database; and a query engine comprising computer hardware, the query engine configured to: receive, from a custom reporting application, a request for entity data of the logical data model, the requested-for entity data being related to first properties of a selected entity of the plurality of entities, access the logical data model to identify two or more physical database tables of the plurality of physical database tables and associated columns in the two or more physical database tables to which the first properties of the selected entity are mapped, construct a query to access the two or more physical database tables in the physical database, pass the query to a database management system to cause the query to be executed on the physical database, receive results of the query from the database management system, and provide the results of the query to the custom reporting application to thereby enable the custom reporting application to generate a report, including the results of the query, for presentation to a user, wherein the plurality of entities of the logical data model are dynamically bound such that updating the logical data model is performed without requiring recompilation of the logical data model or the physical database, thereby enabling the logical data model to be modified at runtime, wherein the logical data model stores semantic relationships between the plurality of entities that mask relational relationships between the plurality of physical database tables, and wherein the logical data model is configured to map an entity of the plurality of entities to multiple database tables of the plurality of physical database tables.