Polystore Systems and DBMSs: Love Marriage or Marriage of Convenience?
Polystore systems allow to combine different heterogeneous data stores in one system and also offer different query languages for accessing data. While this addresses a large number of requirements especially when providing access to heterogeneous data in mixed workloads, most polystore systems are somewhat limited in terms of their functionality. In this paper, we make the case to `upgrade' polystore systems towards full-fledged databases systems, leading to the notion of Poly-DBMSs. We summarize the features of such PolyDBMSs and exemplify the implementation on the basis of our PolyDBMS Polypheny-DB.