Query Federation
Definition
A federated query combines results from separate data sources.
A logical query whose execution involves data from multiple separate sources or query services and integrates partial results into an overall result.
Simply explained
A single query retrieves partial answers from different collections and merges them.
Why it matters in practice
The term improves reliable access to data and knowledge as well as their usable linkage in digital systems.
Example from business
A SPARQL query connects local data with a remote SPARQL endpoint without fully copying the remote dataset.
Limits and pitfalls
- Confusing federation with mere fan-out or underestimating schemas, permissions, freshness, error semantics, and costs of distributed subqueries.
Origin & history
Federated queries evolved from distributed databases and meta-search systems.
Use in mid-sized companies
- Possible application: A SPARQL query connects local data with a remote SPARQL endpoint without fully copying the remote dataset.
Frequently asked questions
What does federated query mean?
A logical query whose execution involves data from multiple separate sources or query services and integrates partial results into an overall result. What mistakes should be avoided? Confusing federation with mere fan-out or underestimating schemas, permissions, freshness, error semantics, and costs of distributed subqueries.
Sources
Source checked on 10.10.2026. Editorial application examples are hypothetical; no evidence of real customer results.
Editorially reviewed on: