1. A computer-implemented method comprising: receiving a set of user-specified criteria; adding to a tree structure, a first set of two or more nodes that are determined based at least in part on the user-specified criteria; associating, with each node in the first set, a separate set of criteria that are based at least in part on the user-specified criteria; displaying the tree structure to which the nodes in the first set have been added; receiving user input that indicates selection of a particular node from the first set; in response to receiving the user input, determining one or more records that satisfy the set of criteria that is associated with the particular node; adding, to the tree structure, a second set of nodes that are generated based at least in part on the one or more records; and displaying the tree structure to which the nodes in the second set have been added.