In Admin > Settings > Search Engine, set the vector database type and search parameters. These settings are shared across Knowledge Bases (KbSphere), Glossaries, and DbSphere.
Search Engine Selection
| Engine | Strengths |
|---|
| Azure AI Search | Azure managed service, hybrid search supported by default |
| PostgreSQL pgvector | PostgreSQL extension, memory-efficient halfvec support |
| Milvus | Large-scale distributed processing, high-performance vector search |
| Elasticsearch | Hybrid search (BM25 + vector), reuse existing ELK stack |
| Google Vertex AI Search | Google Cloud managed search service |
Azure AI Search
pgvector
Milvus
Elasticsearch
Vertex AI Search
| Setting | Description |
|---|
| Endpoint | Azure Search service URL |
| API Key | Admin API Key |
| API Version | API version (e.g., 2024-07-01) |
| Setting | Description |
|---|
| Host | PostgreSQL server address |
| Port | Port number |
| Database | Database name |
| User | Connection username |
| Password | Connection password |
The pgvector extension must be installed in PostgreSQL.
| Setting | Description |
|---|
| URI | Milvus server address |
| Token | Auth token (optional) |
| User | Auth username (optional) |
| Password | Auth password (optional) |
| Setting | Description |
|---|
| URL | Elasticsearch server URL |
| Username | Auth username (optional) |
| Password | Auth password (optional) |
| Index Prefix | Index name prefix (optional) |
| Setting | Description |
|---|
| Project ID | Google Cloud project ID |
| Location | Region |
| Collection | Data store collection |
| Use Global Google Cloud Key | When enabled, uses the global Google Cloud key. When disabled, enter Service Account Key JSON directly below. |
| Service Account Key JSON | JSON input field shown when Use Global Google Cloud Key is disabled. Paste the full service account key JSON. |
Embedding engines and models are configured in the Settings > Documents tab. Vector dimensions must match between search engine and embedding settings.
Search Settings
Configure search result count and reranker.
| Setting | Description | Default |
|---|
| Top K | Vector search result count | 10 |
| Reranker Top K | Result count after reranker | 3 |
| Reranker threshold | Minimum relevance score after reranking (0–1). Results below threshold are filtered | 0.0 |
Reranker Settings (Vertex AI Ranking API)
Configure Vertex AI Ranking API-based reranker to improve search quality.
| Setting | Description |
|---|
| Project ID | Google Cloud project ID (optional — uses Vertex AI Search’s Project ID when unset) |
| Location | Vertex AI Ranking API region |
| Reranker Model | Reranking model to use |
| Authentication | Auth method (Use Global Google Cloud Key toggle or Service Account Key JSON entry) |
Changing the search engine type makes previously indexed data inaccessible. Always plan data migration before changing.
