1. A method comprising: providing, to a client, a definition of an object representing attributes of a first collection of data elements and a definition of one or more modifications to the first collection of data elements, each data element having at least one attribute and at least one modification in common with other data elements from the first collection, the first collection of data elements representing a first table in a database, the modifications to the first collection of data elements corresponding to modifications to the first table in the database; storing side-effects of executing the one or more modifications to the first collection of data elements in a repository, wherein each of the side-effects defines a modification of a data element of a second collection of data elements resulting from executing a corresponding modification to the first collection of data elements, the second collection of data elements representing a second table in the database, the side-effects reflecting modifications to the second table in the database caused by the modifications to the first table in the database; receiving, from the client, a request to execute one of the modifications to the one or more data elements from the first collection; executing the requested modification to the one or more data elements from the first collection; identifying the side-effect corresponding to the requested modification; retrieving the identified side-effect from the repository; and updating a copy of the one or more data elements from the second collection upon execution of the requested modification to the one or more data elements from the first collection, the one or more data elements of the second collection being modified according to the identified side-effect, wherein updating the copy provides consistency between the copy of the data elements from the second collection representing the second table in the database with the modified data elements from the first collection representing the first table in the database.