Querying Multiple Datasets
Pass multiple dataset IDs to search across them in a single call:Single-Model vs Multi-Model
Same embedding model
When all datasets use the same model (e.g.,text-embedding-3-small):
- Query text is embedded once
- Results are ranked by raw similarity score (0–1, higher = more relevant)
- Scores are directly comparable across datasets
Different embedding models
When datasets use different models (e.g., one usestext-embedding-3-small, another uses embed-v4.0):
- Query text is embedded once per unique model (in parallel)
- Results are ranked by Reciprocal Rank Fusion (RRF)
- RRF uses
1/(k + rank)where rank is the result’s position within its dataset - This is fair across models because it only considers rank order, not raw scores
embedding_model field appears on results only in multi-model queries so you can see which model produced each result.
Partial Failures
If one dataset’s vector DB is unreachable, the other datasets still return results. Checkresponse.warnings for details:
Pre-Computed Vectors
When usingvector instead of text:
- All datasets must use the same embedding model — the server can’t split a single vector across different models (returns 400 if they differ)
- Vector dimension must match the model’s expected dimension