Class VercelPostgres

Class that provides an interface to a Vercel Postgres vector database. It extends the VectorStore base class and implements methods for adding documents and vectors and performing similarity searches.

Hierarchy

VectorStore
- VercelPostgres

Constructors

constructor

new VercelPostgres(embeddings, config): VercelPostgres
Parameters
- embeddings: EmbeddingsInterface
- config: VercelPostgresFields
Returns VercelPostgres
Overrides VectorStore.constructor
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:63

Properties

FilterType

FilterType: Metadata

client

client: VercelPoolClient

contentColumnName

contentColumnName: string

embeddings

embeddings: EmbeddingsInterface

Embeddings interface for generating vector embeddings from text queries, enabling vector-based similarity searches.

`Optional`filter

filter?: Metadata

idColumnName

idColumnName: string

metadataColumnName

metadataColumnName: string

pool

pool: VercelPool

tableName

tableName: string

vectorColumnName

vectorColumnName: string

Methods

addDocuments

addDocuments(documents, options?): Promise<string[]>
Method to add documents to the vector store. It converts the documents into vectors, and adds them to the store.
Parameters
- documents: Document<Record<string, any>>[]
  Array of Document instances.
- Optionaloptions: {
  ids?: string[];
  }
  - Optionalids?: string[]
Returns Promise<string[]>
Promise that resolves when the documents have been added.
Overrides VectorStore.addDocuments
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:120

addVectors

addVectors(vectors, documents, options?): Promise<string[]>
Method to add vectors to the vector store. It converts the vectors into rows and inserts them into the database.
Parameters
- vectors: number[][]
  Array of vectors.
- documents: Document<Record<string, any>>[]
  Array of Document instances.
- Optionaloptions: {
  ids?: string[];
  }
  - Optionalids?: string[]
Returns Promise<string[]>
Promise that resolves when the vectors have been added.
Overrides VectorStore.addVectors
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:191

asRetriever

asRetriever(kOrFields?, filter?, callbacks?, tags?, metadata?, verbose?): VectorStoreRetriever<VercelPostgres>
Creates a VectorStoreRetriever instance with flexible configuration options.
Parameters
- OptionalkOrFields: number | Partial<VectorStoreRetrieverInput<VercelPostgres>>
  If a number is provided, it sets the k parameter (number of items to retrieve).
  - If an object is provided, it should contain various configuration options.
- Optionalfilter: Metadata
  Optional filter criteria to limit the items retrieved based on the specified filter type.
- Optionalcallbacks: Callbacks
  Optional callbacks that may be triggered at specific stages of the retrieval process.
- Optionaltags: string[]
  Tags to categorize or label the VectorStoreRetriever. Defaults to an empty array if not provided.
- Optionalmetadata: Record<string, unknown>
  Additional metadata as key-value pairs to add contextual information for the retrieval process.
- Optionalverbose: boolean
  If true, enables detailed logging for the retrieval process. Defaults to false.
Returns VectorStoreRetriever<VercelPostgres>
- A configured VectorStoreRetriever instance based on the provided parameters.
Example
Basic usage with a k value:
```
const retriever = myVectorStore.asRetriever(5);
```
Usage with a configuration object:
```
const retriever = myVectorStore.asRetriever({
  k: 10,
  filter: myFilter,
  tags: ['example', 'test'],
  verbose: true,
  searchType: 'mmr',
  searchKwargs: { alpha: 0.5 },
});
```
Inherited from VectorStore.asRetriever
- Defined in langchain-core/dist/vectorstores.d.ts:596

delete

delete(params): Promise<void>
Deletes documents from the vector store based on the specified parameters.
Parameters
- params: {
  deleteAll?: boolean;
  ids?: string[];
  }
  - OptionaldeleteAll?: boolean
  - Optionalids?: string[]
Returns Promise<void>
A promise that resolves once the deletion is complete.
Overrides VectorStore.delete
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:300

end

end(): Promise<void>
Closes all the clients in the pool and terminates the pool.

Returns Promise<void>
Promise that resolves when all clients are closed and the pool is terminated.
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:389

ensureTableInDatabase

ensureTableInDatabase(): Promise<void>
Method to ensure the existence of the table in the database. It creates the table if it does not already exist.

Returns Promise<void>
Promise that resolves when the table has been ensured.
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:319

`Protected`generatePlaceholderForRowAt

generatePlaceholderForRowAt(row, index): string
Generates the SQL placeholders for a specific row at the provided index.
Parameters
- row: (string | Record<string, any>)[]
- index: number
  The index of the row for which placeholders need to be generated.
Returns string
The SQL placeholders for the row values.
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:139

`Optional`maxMarginalRelevanceSearch

maxMarginalRelevanceSearch(query, options, _callbacks): Promise<DocumentInterface<Record<string, any>>[]>
Return documents selected using the maximal marginal relevance. Maximal marginal relevance optimizes for similarity to the query AND diversity among selected documents.
Parameters
- query: string
  Text to look up documents similar to.
- options: MaxMarginalRelevanceSearchOptions<Metadata>
- _callbacks: undefined | Callbacks
Returns Promise<DocumentInterface<Record<string, any>>[]>
- List of documents selected by maximal marginal relevance.
Inherited from VectorStore.maxMarginalRelevanceSearch
- Defined in langchain-core/dist/vectorstores.d.ts:527

`Protected`runInsertQuery

runInsertQuery(rows, useIdColumn): Promise<QueryResult<any>>
Constructs the SQL query for inserting rows into the specified table.
Parameters
- rows: (string | Record<string, any>)[][]
  The rows of data to be inserted, consisting of values and records.
- useIdColumn: boolean
Returns Promise<QueryResult<any>>
The complete SQL INSERT INTO query string.
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:155

similaritySearch

similaritySearch(query, k?, filter?, _callbacks?): Promise<DocumentInterface<Record<string, any>>[]>
Searches for documents similar to a text query by embedding the query and performing a similarity search on the resulting vector.
Parameters
- query: string
  Text query for finding similar documents.
- Optionalk: number
  Number of similar results to return. Defaults to 4.
- Optionalfilter: Metadata
  Optional filter based on FilterType.
- Optional_callbacks: Callbacks
  Optional callbacks for monitoring search progress
Returns Promise<DocumentInterface<Record<string, any>>[]>
A promise resolving to an array of DocumentInterface instances representing similar documents.
Inherited from VectorStore.similaritySearch
- Defined in langchain-core/dist/vectorstores.d.ts:499

similaritySearchVectorWithScore

similaritySearchVectorWithScore(query, k, filter?): Promise<[Document<Record<string, any>>, number][]>
Method to perform a similarity search in the vector store. It returns the k most similar documents to the query vector, along with their similarity scores.
Parameters
- query: number[]
  Query vector.
- k: number
  Number of most similar documents to return.
- Optionalfilter: Metadata
  Optional filter to apply to the search.
Returns Promise<[Document<Record<string, any>>, number][]>
Promise that resolves with an array of tuples, each containing a Document and its similarity score.
Overrides VectorStore.similaritySearchVectorWithScore
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:244

similaritySearchWithScore

similaritySearchWithScore(query, k?, filter?, _callbacks?): Promise<[DocumentInterface<Record<string, any>>, number][]>
Searches for documents similar to a text query by embedding the query, and returns results with similarity scores.
Parameters
- query: string
  Text query for finding similar documents.
- Optionalk: number
  Number of similar results to return. Defaults to 4.
- Optionalfilter: Metadata
  Optional filter based on FilterType.
- Optional_callbacks: Callbacks
  Optional callbacks for monitoring search progress
Returns Promise<[DocumentInterface<Record<string, any>>, number][]>
A promise resolving to an array of tuples, each containing a document and its similarity score.
Inherited from VectorStore.similaritySearchWithScore
- Defined in langchain-core/dist/vectorstores.d.ts:511

toJSON

toJSON(): Serialized
Returns Serialized
Inherited from VectorStore.toJSON
- Defined in langchain-core/dist/load/serializable.d.ts:69

toJSONNotImplemented

toJSONNotImplemented(): SerializedNotImplemented
Returns SerializedNotImplemented
Inherited from VectorStore.toJSONNotImplemented
- Defined in langchain-core/dist/load/serializable.d.ts:70

`Static`fromDocuments

fromDocuments(docs, embeddings, dbConfig?): Promise<VercelPostgres>
Static method to create a new VercelPostgres instance from an array of Document instances. It adds the documents to the store.
Parameters
- docs: Document<Record<string, any>>[]
  Array of Document instances.
- embeddings: EmbeddingsInterface
  Embeddings instance.
- OptionaldbConfig: Partial<VercelPostgresFields> & {
  postgresConnectionOptions?: VercelPostgresPoolConfig;
  }
Returns Promise<VercelPostgres>
Promise that resolves with a new instance of VercelPostgres.
Overrides VectorStore.fromDocuments
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:371

`Static`fromTexts

fromTexts(texts, metadatas, embeddings, dbConfig?): Promise<VercelPostgres>
Static method to create a new VercelPostgres instance from an array of texts and their metadata. It converts the texts into Document instances and adds them to the store.
Parameters
- texts: string[]
  Array of texts.
- metadatas: object | object[]
  Array of metadata objects or a single metadata object.
- embeddings: EmbeddingsInterface
  Embeddings instance.
- OptionaldbConfig: Partial<VercelPostgresFields> & {
  postgresConnectionOptions?: VercelPostgresPoolConfig;
  }
Returns Promise<VercelPostgres>
Promise that resolves with a new instance of VercelPostgres.
Overrides VectorStore.fromTexts
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:341

`Static`initialize

initialize(embeddings, config?): Promise<VercelPostgres>
Static method to create a new VercelPostgres instance from a connection. It creates a table if one does not exist, and calls connect to return a new instance of VercelPostgres.
Parameters
- embeddings: EmbeddingsInterface
  Embeddings instance.
- Optionalconfig: Partial<VercelPostgresFields> & {
  postgresConnectionOptions?: VercelPostgresPoolConfig;
  }
Returns Promise<VercelPostgres>
A new instance of VercelPostgres.
- Defined in libs/langchain-community/src/vectorstores/vercel_postgres.ts:90

Class VercelPostgres

Hierarchy

Index

Constructors

Properties

Methods

Constructors

constructor

Parameters

Returns VercelPostgres

Properties

FilterType

client

contentColumnName

embeddings

Optionalfilter

idColumnName

metadataColumnName

pool

tableName

vectorColumnName

Methods

addDocuments

Parameters

Optionalids?: string[]

Returns Promise<string[]>

addVectors

Parameters

Optionalids?: string[]

Returns Promise<string[]>

asRetriever

Parameters

Returns VectorStoreRetriever<VercelPostgres>

Example

delete

Parameters

OptionaldeleteAll?: boolean

Optionalids?: string[]

Returns Promise<void>

end

Returns Promise<void>

ensureTableInDatabase

Returns Promise<void>

ProtectedgeneratePlaceholderForRowAt

Parameters

Returns string

OptionalmaxMarginalRelevanceSearch

Parameters

Returns Promise<DocumentInterface<Record<string, any>>[]>

ProtectedrunInsertQuery

Parameters

Returns Promise<QueryResult<any>>

similaritySearch

Parameters

Returns Promise<DocumentInterface<Record<string, any>>[]>

similaritySearchVectorWithScore

Parameters

Returns Promise<[Document<Record<string, any>>, number][]>

similaritySearchWithScore

Parameters

Returns Promise<[DocumentInterface<Record<string, any>>, number][]>

toJSON

Returns Serialized

toJSONNotImplemented

Returns SerializedNotImplemented

StaticfromDocuments

Parameters

Returns Promise<VercelPostgres>

StaticfromTexts

Parameters

Returns Promise<VercelPostgres>

Staticinitialize

Parameters

Returns Promise<VercelPostgres>

Settings

On This Page

`Optional`filter

`Optional`ids?: string[]

`Optional`ids?: string[]

`Optional`deleteAll?: boolean

`Optional`ids?: string[]

`Protected`generatePlaceholderForRowAt

`Optional`maxMarginalRelevanceSearch

`Protected`runInsertQuery

`Static`fromDocuments

`Static`fromTexts

`Static`initialize