Information Retrieval using Dynamic Indexing

Since the demand for information retrieval increases quickly, indexing structures became an important issue to support fast information retrieval. According to the work in this paper, a new data structure called Dynamic Ordered Multi-field Index (DOMI) for information retrieval has been introduced. It is based on radix trees organized in segments in addition to a hash table to point to the roots of each segment, where each segment is dedicated to store the values of a single field. The hash table is used to access the needed segments directly without traversing the upper segments. So, DOMI improves look-up performance for queries addressing to a single field. In the case of multiple queries addressing, each segment of the radix tree is traversed sequentially without visiting the unrelated branches. The use of segmentation for the proposed DOMI provides flexibility for minimizing communication overhead in the distributed system. Every field in the radix tree is represented by one segment, where each segment can be stored as one block. Moreover, the proposed DOMI consumes less space comparing to indexes which are built using B or B+ trees. Hence, it is more suitable for intensive-data such as Big Data.