1. A computer implemented method of generating a data source model for heterogeneous data sources, the method comprising: defining a first interface for a first abstract sub-model of a first sub-model without defining a data source structure for the first sub-model responsive to user input through a user interface; defining a second interface for a second abstract sub-model of a second sub-model without defining a data source structure for the second sub-model responsive to user input through the user interface; defining a connection between the first interface of the first abstract sub-model and the second interface of the second abstract sub-model; defining a first data source structure for the first sub-model separately from the first abstract sub-model, wherein the first data source structure defines a coupling to the first interface of the first abstract sub-model; defining a second data source structure for the second sub-model separately from the second abstract sub-model, wherein the second data source structure defines a coupling to the second interface, wherein the first and second data source structures are heterogeneous data source structures having respective different data source structure types, and wherein at least one of the first and second data source structure types comprises a database structure; after defining the first and second data source structures for the first and second sub-models, generating, by a processor, a unified data source model including the first and second sub-models having the respective first and second data source structures and having the respective first and second interfaces of the first and second abstract sub-models, wherein the first and second sub-models are coupled through the connection defined between the respective first and second interfaces of the first and second abstract sub-models; and rendering the unified data source model including the first and second sub-models having the respective first and second data source structures and coupled through the connection defined between the first and second interfaces on a display.
1. A computer implemented method of generating a data source model for heterogeneous data sources, the method comprising: defining a first interface for a first abstract sub-model of a first sub-model without defining a data source structure for the first sub-model responsive to user input through a user interface; defining a second interface for a second abstract sub-model of a second sub-model without defining a data source structure for the second sub-model responsive to user input through the user interface; defining a connection between the first interface of the first abstract sub-model and the second interface of the second abstract sub-model; defining a first data source structure for the first sub-model separately from the first abstract sub-model, wherein the first data source structure defines a coupling to the first interface of the first abstract sub-model; defining a second data source structure for the second sub-model separately from the second abstract sub-model, wherein the second data source structure defines a coupling to the second interface, wherein the first and second data source structures are heterogeneous data source structures having respective different data source structure types, and wherein at least one of the first and second data source structure types comprises a database structure; after defining the first and second data source structures for the first and second sub-models, generating, by a processor, a unified data source model including the first and second sub-models having the respective first and second data source structures and having the respective first and second interfaces of the first and second abstract sub-models, wherein the first and second sub-models are coupled through the connection defined between the respective first and second interfaces of the first and second abstract sub-models; and rendering the unified data source model including the first and second sub-models having the respective first and second data source structures and coupled through the connection defined between the first and second interfaces on a display. 8. The computer implemented method of claim 1 further comprising: defining a third interface for the first abstract sub-model of the first sub-model without defining a data source structure for the first sub-model responsive to user input through a user interface; defining a fourth interface for a third abstract sub-model of a third sub-model without defining a data source structure for the third sub-model responsive to user input through the user interface; defining a connection between the third interface of the first abstract sub-model and the fourth interface of the third abstract sub-model; and defining a third data source structure for the third sub-model responsive to user input through the user interface wherein the third data source structure defines a coupling to the fourth interface of the third abstract sub-model; wherein generating the unified data source model comprises generating the unified data source model including the first, second, and third sub-models having the respective first, second, and third data source structures, the first sub-model having the first and third interfaces of the first abstract sub-model, the third sub-model having the fourth interface of the third abstract sub-model, wherein the first and second sub-models are coupled through the connection between the first and second interfaces and wherein the first and third sub-models are coupled through the connection between the third and fourth interfaces.