Efficient structural joins with on-the-fly indexing

Previous work on structural joins mostly focuses on maintaining offline indexes on disks. Most of them also require the elements in both sets to be sorted. In this paper, we study an on-the-fly, in-memory indexing approach to structural joins. There is no need to sort the elements or maintain indexes on disks. We identify the similarity between the structural join problem and the stabbing query problem, and extend a main memory-based indexing technique for stabbing queries to structural joins.