> The reason for this is: dedicated tools are always better, faster, and more feature-rich. Depends. Polyglot persistence has the benefit of letting you use th

> The reason for this is: dedicated tools are always better, faster, and more feature-rich. Depends. Polyglot persistence has the benefit of letting you use the "best tool for the job" for each job but that benefit can fall apart if you have cross-cutting concerns. If you need to query across different storages you often end up compromising on several of the initial benefits (e.g. performance from passing data between storages or resource use and consistency from duplicating critical data). For example, you could store your graph data in Neo4J and your document data in MongoDB but good luck doing graph queries that need to access the document data. OR you could use something like Tiger or Arango that's a graph database that can also store data other than pure edges.