A data processing system comprising: - a data warehouse having stored therein a set of database tables (104, 106, 108,..) including first and second database tables, - a plurality of application programs , - a user interface for selection of an application program from the plurality of application programs, and from which a manual selection from a user is received of a combination of the first and second database tables of the set of database tables and from which a manual selection from a user is received of particular combinations of first entries of a first entity type from the first database table with second entries of a second entity type from the second database table, - means for generating a combination database table (120, ...) for storing the combinations of the selected first and second entries, the combination database table including a first column of the first entity type and a second column of the second entity type, the combination database table storing the combination entries based on the manual selection, - means for storing the combination database table, wherein the selected application program is operable to access the means for storing in order to perform a read access on the combination database table for processing the combination database table; - a mapping table which is stored in the data processing system for each of the application programs that specifies which ones of the database tables can be combined for the purpose of processing the resultant combination table by the respective application program, the user interface being operable to read the mapping table assigned to the selected application program in order to determine allowed database table combinations for the selected application program once the application program has been selected by the user, and wherein the user interface is further operable to only display such database table combinations for selection of data elements therefrom which have been previously determined to be allowed database table combinations for the selected application program. - a data warehouse having stored therein a set of database tables (104, 106, 108,..) including first and second database tables, - a plurality of application programs , - a user interface for selection of an application program from the plurality of application programs, and from which a manual selection from a user is received of a combination of the first and second database tables of the set of database tables and from which a manual selection from a user is received of particular combinations of first entries of a first entity type from the first database table with second entries of a second entity type from the second database table, - means for generating a combination database table (120, ...) for storing the combinations of the selected first and second entries, the combination database table including a first column of the first entity type and a second column of the second entity type, the combination database table storing the combination entries based on the manual selection, - means for storing the combination database table, wherein the selected application program is operable to access the means for storing in order to perform a read access on the combination database table for processing the combination database table; - a mapping table which is stored in the data processing system for each of the application programs that specifies which ones of the database tables can be combined for the purpose of processing the resultant combination table by the respective application program, the user interface being operable to read the mapping table assigned to the selected application program in order to determine allowed database table combinations for the selected application program once the application program has been selected by the user, and <EOS>