Abstract: A method and system for visually constructing and displaying relational queries on a tabular interface. A query is a relational expression that defines how to extract and process data from a data source. A data source could be a relational database, or other sources where data can be extracted and converted to tables consisting of column. A query may be composed from other queries using relational operators such as join and union, potentially resulting in a complex intertwined tree-like structure. The invention provides methods of representing hierarchical query structure on a tabular interface using nested table structures, and steps for constructing and manipulating the structure using spatial relationships. Unique to this method is the ability to work with highly complex hierarchical tree-link structure using a simple two-dimensional table. Also unique to this method is the ability to change the hierarchical structure using relative spatial placement of the tables.