A Method carried out in a computer system including a spreadsheet file having a sheet with lines and columns, wherein columns represent fields, the sheet having a header portion having a designation line with a field designation for each column, a data portion, wherein each line includes a record, the method including:
/a/ identifying a single reference field,
/b/ allocating a field type to fields other than the reference field, the field type belonging to a set of field type including attribute, parent, and flow,
/c/ defining a link, for each field with a type, which establishes a link with another linked field, in particular a parent/child link,
/d/ building a hierarchical model representing the parent/child links,
/f/ generating a graphical hierarchical multilevel representation of the sheet content, with graphical views showing one or more hierarchical levels and displaying the representation on the display.