Yes. The question is really how and if it is supporting your arguments.
For example, if you want to replicate their method or refine it, then most definitely yes.
If it is seminal work (unsure of this) and their terminology supports the problem definition, then absolutely yes.
If you want to identify you contributions with respect to other work, then most likely. The question is then, how similar are their problem definition, their method or results to your problem definition, method and results. How much you can use their work in this aspect depends on how similar your work is compared to their work.
Yes, in case that you could not find any newer and better method.
You should check from papers citing this one. If there is any newer and better method, the new paper should cite this one in order to compare their work.
Their problem definition is similar to mine. Though there are many benchmarking papers out there, this one performed a generic one; not limited to relational databases. Since my study is to evaluate relational and document database, I am looking for benchmarks that I can use to evaluate both dbs fairly. And I think this paper is a good reference. Will that be fine?