![[assets/ex_customscanforeignscan.png|256]]
- **Description**: Scans foreign tables or data sources
- **Performance**: Depends on the custom implementation.
- **Factors**: Implementation-specific costs.
- **Cost**: Custom/foreign cost model.
- ![[assets/ex_foreign_scan.svg|200x200]]
- **Operates on**: [[Structures/Result Set]]
- **Workloads**:
- [[Workloads/Client]]
- [[Workloads/Sub/ClientRead]]
- [[Workloads/Sub/ClientWrite]]
- [[Workloads/IO]]
- [[Workloads/Sub/DataFileRead]]
- [[Workloads/LWLock]]
- [[Workloads/Sub/BufferContent]]