Querying Vectors - Upstash Documentation

Now that our database contains data, we want to query it.

There are several ways to query the database, depending on the type of index you have configured.

Querying

You can query your vector index for similar vectors.

Below, we will learn how to use the SDK to query Dense, Sparse, and Hybrid indexes.

You can read more about Sparse Indexes and Hybrid Indexes on our docs.

Dense Indexes

We’ll use the query() method to instruct the SDK to query vectors from Upstash Vector.

use Upstash\Vector\Index;
use Upstash\Vector\VectorQuery;

$index = new Index(
  url: "<UPSTASH_VECTOR_REST_URL>",
  token: "<UPSTASH_VECTOR_REST_TOKEN>",
);

$results = $index->query(new VectorQuery(
  vector: [0.1, 0.2, ...], // "..." represents the dimension size of your vector index.
  topK: 15, // topK is the limit number of records we want to be returned.
  includeMetadata: true, // (optional) if true the query results will contain metadata.
  includeVectors: true, // (optional) if true the query results will contain the indexed vectors.
  includeData: true, // (optional) if true the query results will contain the string data.
  filter: '', // (optional) if set, the query results will be filtered by the given filter.
));

The dimension of the query vector must match the dimension of your index.

The score returned from query requests is a normalized value between 0 and 1, where 1 indicates the highest similarity and 0 the lowest regardless of the similarity function used.

Sparse Indexes

We can also use the query() method to instruct the SDK to query our Sparse index, as shown below:

use Upstash\Vector\Index;
use Upstash\Vector\VectorQuery;
use Upstash\Vector\SparseVector;

$index = new Index(
  url: "<UPSTASH_VECTOR_REST_URL>",
  token: "<UPSTASH_VECTOR_REST_TOKEN>",
);

$results = $index->query(new VectorQuery(
  sparseVector: new SparseVector(
    indices: [1, 2, 3],
    values: [5.0, 6.0, 7.0],
  ),
  topK: 15,
));

Sparse indexes can only be queried using sparse vectors. If you attempt to pass a regular vector in the query, the SDK will throw an exception.

Hybrid Indexes

Hybrid indexes work the same way; they also use the query() method to query our index, as shown below:

use Upstash\Vector\Index;
use Upstash\Vector\VectorQuery;
use Upstash\Vector\SparseVector;

$index = new Index(
  url: "<UPSTASH_VECTOR_REST_URL>",
  token: "<UPSTASH_VECTOR_REST_TOKEN>",
);

$results = $index->query(new VectorQuery(
  vector: [0.1, 0.2, ...],
  sparseVector: new SparseVector(
    indices: [1, 2, 3],
    values: [5.0, 6.0, 7.0],
  ),
  topK: 15,
));

Embedding Models

Query Data

If your index is configured with one of our embedding models, you can query the index using a simple string, which will be automatically converted into vector embeddings. See the example below:

use Upstash\Vector\Index;
use Upstash\Vector\DataQuery;

$index = new Index(
  url: "<UPSTASH_VECTOR_REST_URL>",
  token: "<UPSTASH_VECTOR_REST_TOKEN>",
);

$results = $index->queryData(new DataQuery(
  data: 'What is the capital of France?',
  topK: 1, // to only return 1 result.
  includeData: true,
));

If your index is not configured with an embedding model, this call will throw an exception.

You can read more about Embedding Models on our docs.

Metadata Filtering

Data stored in indexes on Upstash Vector can be populated with metadata, which can then be used for filtering vectors.

Our SDK makes it easy to filter vectors based on their metadata values. Check out the example below:

use Upstash\Vector\Index;
use Upstash\Vector\VectorQuery;

$index = new Index(
  url: "<UPSTASH_VECTOR_REST_URL>",
  token: "<UPSTASH_VECTOR_REST_TOKEN>",
);

$results = $index->query(new VectorQuery(
  vector: [0.1, 0.2, ...],
  topK: 15,
  filter: "country = 'PT' AND continent = 'EU'"
));

You can read more about Metadata Filtering on our docs.

​Querying

​Dense Indexes

​Sparse Indexes

​Hybrid Indexes

​Embedding Models

​Query Data

​Metadata Filtering