An aspect of the present invention simplifies grouping of data items previously stored in a database, the data items being stored in the form of rows and columns in respective tables (in the database). In one embodiment, a system displays a cross product of values from two or more columns in the form of multiple lines, where each line contains a respective value from each of the two or more columns to specify a corresponding criterion (combination of values). In response to receiving inputs indicating the respective groups for each of the lines, the system determines a group for each data item (stored in the database) based on the received inputs. A user is accordingly required to only specify the desired groups corresponding to various combinations of values of the columns to cause grouping of data items in the database.