15. An integration server system, comprising: a processor that executes instructions stored in a data storage medium; a database that stores data accessible to the processor; a generator that creates a database schema in response to a model description, the database schema including at least one table and configured to store a set of data object instances in the database; a metadata model representing a configuration of the set of data object instances in the database schema; a model application programming interface that provides a client application with access to the set of data object instances as separate data objects; and a metadata application programming interface that provides a client application with access to definitions for the set of data object directly within the database schema instances via the metadata model, wherein the database schema utilizes an ordered sequence for preserving an ordered association between the set of data object instances, a random sequence value being generated for a new data object instance to be inserted into the ordered sequence, the random sequence value being generated relative to an average of sequence values of existing data object instances immediately adjacent to a point of insertion in the ordered sequence, the generation of a random sequence value enabling the client application and any additional application able to concurrently insert a data object instances into the ordered sequence.
15. An integration server system, comprising: a processor that executes instructions stored in a data storage medium; a database that stores data accessible to the processor; a generator that creates a database schema in response to a model description, the database schema including at least one table and configured to store a set of data object instances in the database; a metadata model representing a configuration of the set of data object instances in the database schema; a model application programming interface that provides a client application with access to the set of data object instances as separate data objects; and a metadata application programming interface that provides a client application with access to definitions for the set of data object directly within the database schema instances via the metadata model, wherein the database schema utilizes an ordered sequence for preserving an ordered association between the set of data object instances, a random sequence value being generated for a new data object instance to be inserted into the ordered sequence, the random sequence value being generated relative to an average of sequence values of existing data object instances immediately adjacent to a point of insertion in the ordered sequence, the generation of a random sequence value enabling the client application and any additional application able to concurrently insert a data object instances into the ordered sequence. 18. The integration server system of claim 15 , wherein the generator creates a database constraint adapted to ensure that the set of data object instances include a set of valid attribute values.