STLIS: A Scalable Two-Level Index Scheme for Big Data in IoT

Table 2

Query response time on LUBM50 (seconds).

	Q1	Q2	Q3	Q4	Q5	Q6	Q7
RDF-3X	3.09	0.37	2.34	0.45	0.47	1.38	3.28
Bitmat	3.51	0.51	2.37	1.03	0.59	2.69	3.95
TripleBit	2.43	0.25	1.07	0.86	0.43	0.79	0.66
STLIS	0.38	0.42	0.29	0.78	0.53	0.19	0.57