1. A computer-implemented method of generating a physical design from a logical design for data integration, comprising: receiving a logical design of a data integration mapping; applying a plurality of rules to the logical design, wherein the plurality of rules are ranked and the ranking is used to resolve a conflict among the plurality of rules by applying a rule with a higher rank over a rule with a lower rank; wherein the plurality of rules comprise transformation operations that are allowable by a plurality of execution units and the plurality of rules are pushed to the plurality of execution units; generating a default physical design comprising the plurality of execution units based on the logical design; grouping the plurality of execution units into one or more execution unit groups, wherein each execution unit group includes independent execution units which can execute in parallel; receiving changes to the default physical design, wherein the changes redefine one or more of the plurality of execution units; dynamically generating a second physical design based on the changes to the default physical design; and associating the second physical design with the logical design, wherein the logical design can be associated with a plurality of different physical designs, wherein a first transformation operation is pushed to an execution unit in the default physical design, and a second transformation operation that is distinctly different from the first transformation operation is pushed to an execution unit in the second physical design.