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

Table 3

Query response time on LUBM2000 (seconds).

	Q1	Q2	Q3	Q4	Q5	Q6	Q7
RDF-3X	280.65	4.179	153.91	5.036	3.67	10.344	143.35
Bitmat	15.48	0.96	9.56	1.54	1.24	5.98	9.78
TripleBit	23.029	3.062	6.38	6.056	5.011	12.105	35.799
STLIS	6.67	0.83	4.54	1.03	1.44	2.37	3.38