What the data for this category looks like
Daily documents for this category typically include maintenance plans, patrol logs, defect handling forms, road construction permits, road damage compensation forms, and more. Data is generally sourced from highway maintenance management systems, bridge and tunnel monitoring systems, road patrol management systems, and traffic flow monitoring data. The update frequency is daily. Most documents use structured fields as their primary structure, including facility ID, patrol time, defect type, handling measures, permit number, and other fields. Some unstructured documents have on-site photos or monitoring data attached.
What constraints these characteristics impose on the knowledge base retrieval and recall workflow
The high-frequency daily data requires the knowledge base to support incremental synchronization mechanisms, to avoid excessive resource consumption from full re-imports. Mixed multi-source heterogeneous data—structured fields and unstructured documents coexisting—requires retrieval logic that supports field matching across different formats. This ensures that defect descriptions in patrol logs can be associated with the scope of road construction permits for recall. A single file often involves multiple related documents, so enough relevant results must be retrieved to avoid missing key evidence. Additionally, there are many domain-specific terms, so retrieval must precisely match requirements for specific scenarios, preventing generalized results from interfering with review and judgment.
How to set configurations
Reference only; verify against the target FastGPT release and deployment documentation.
| Configuration Item | Recommended Value | Rationale |
|---|---|---|
similarity | 0.72–0.80 | Matches recall accuracy for professional terms in the highway maintenance domain, prevents low-relevance results from being included |
limit | Top 8 entries | Covers multiple related documents for a single file, while controlling context length |
searchMode | hybrid | Combines keyword and semantic retrieval, adapts to mixed data of structured fields and unstructured documents |
usingReRank | Enabled | Performs secondary ranking on initial recall results, filters out irrelevant daily maintenance records from patrol logs |
datasetSearchUsingExtensionQuery | Enabled | Automatically expands professional term queries, such as associating "pothole" with "pavement defect" and "maintenance handling" |
collectionIds | Configured by business domain | Only retrieves knowledge base collections related to highway maintenance and road property and right management, excludes irrelevant business data |
Three Common Mistakes
- Symptom: When creating a knowledge base using the URL of an internal highway maintenance management system, the backend returns the
cannot fetch internal urlerror. Cause: The internal network access whitelist is not configured, or the FastGPT deployment environment cannot access the interface of the internal system. - Symptom: When clicking chunk preview for some PDF-format defect handling forms or road construction permit documents, a prompt appears indicating that file content cannot be read. Cause: The PDF contains encrypted content, non-standard font embedding, or the document parsing plugin does not adapt to the special typesetting of highway maintenance documents.
- Symptom: The number of collections that can be associated with the open-source knowledge base deployed locally is limited to 30, and cannot be expanded. Cause: The collection upper limit parameter in the deployment configuration is not modified, and the default open-source version has a basic quantity limit.
How to confirm the configuration is complete
- Submit a query related to road construction permits, check whether the recall results include relevant patrol logs, defect handling forms and other associated documents.
- View the knowledge base synchronization logs, confirm that the daily incremental update tasks are running normally, with no failed records.
- Test professional term retrieval, enter "bridge and tunnel defect", confirm that the recall results include relevant data from bridge and tunnel monitoring systems.
- Check the configuration item parameters, confirm that
usingReRankanddatasetSearchUsingExtensionQueryare enabled.
The values given are common starting points and should be measured against the reader's own samples.
Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-28.