Package dev.langchain4j.store.embedding.pgvector

Class PgVectorEmbeddingStore

java.lang.Object

dev.langchain4j.store.embedding.pgvector.PgVectorEmbeddingStore

All Implemented Interfaces:

EmbeddingStore<TextSegment>

public class PgVectorEmbeddingStore
extends Object
implements EmbeddingStore<TextSegment>

PGVector EmbeddingStore Implementation

Only cosine similarity is used. Only ivfflat index is used.

Constructor Summary

Constructors

Constructor	Description
PgVectorEmbeddingStore(String host, Integer port, String user, String password, String database, String table, Integer dimension, Boolean useIndex, Integer indexListSize, Boolean createTable, Boolean dropTableFirst)	All args constructor for PgVectorEmbeddingStore Class

Method Summary

Modifier and Type	Method	Description
String	add(Embedding embedding)	Adds a given embedding to the store.
String	add(Embedding embedding, TextSegment textSegment)	Adds a given embedding and the corresponding content that has been embedded to the store.
void	add(String id, Embedding embedding)	Adds a given embedding to the store.
List<String>	addAll(List<Embedding> embeddings)	Adds multiple embeddings to the store.
List<String>	addAll(List<Embedding> embeddings, List<TextSegment> embedded)	Adds multiple embeddings and their corresponding contents that have been embedded to the store.
List<EmbeddingMatch<TextSegment>>	findRelevant(Embedding referenceEmbedding, int maxResults, double minScore)	Finds the most relevant (closest in space) embeddings to the provided reference embedding.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface dev.langchain4j.store.embedding.EmbeddingStore

findRelevant, findRelevant, findRelevant

Constructor Details

PgVectorEmbeddingStore

public PgVectorEmbeddingStore(String host,
 Integer port,
 String user,
 String password,
 String database,
 String table,
 Integer dimension,
 Boolean useIndex,
 Integer indexListSize,
 Boolean createTable,
 Boolean dropTableFirst)

All args constructor for PgVectorEmbeddingStore Class

Parameters:

host - The database host

port - The database port

user - The database user

password - The database password

database - The database name

table - The database table

dimension - The vector dimension

useIndex - Should use IVFFlat index

indexListSize - The IVFFlat number of lists

createTable - Should create table automatically

dropTableFirst - Should drop table first, usually for testing

Method Details

add

public String add(Embedding embedding)

Adds a given embedding to the store.

Specified by:

add in interface EmbeddingStore<TextSegment>

Parameters:

embedding - The embedding to be added to the store.

Returns:

The auto-generated ID associated with the added embedding.

add

public void add(String id,
 Embedding embedding)

Adds a given embedding to the store.

Specified by:

add in interface EmbeddingStore<TextSegment>

Parameters:

id - The unique identifier for the embedding to be added.

embedding - The embedding to be added to the store.

add

public String add(Embedding embedding,
 TextSegment textSegment)

Adds a given embedding and the corresponding content that has been embedded to the store.

Specified by:

add in interface EmbeddingStore<TextSegment>

Parameters:

embedding - The embedding to be added to the store.

textSegment - Original content that was embedded.

Returns:

The auto-generated ID associated with the added embedding.

addAll

public List<String> addAll(List<Embedding> embeddings)

Adds multiple embeddings to the store.

Specified by:

addAll in interface EmbeddingStore<TextSegment>

Parameters:

embeddings - A list of embeddings to be added to the store.

Returns:

A list of auto-generated IDs associated with the added embeddings.

addAll

public List<String> addAll(List<Embedding> embeddings,
 List<TextSegment> embedded)

Adds multiple embeddings and their corresponding contents that have been embedded to the store.

Specified by:

addAll in interface EmbeddingStore<TextSegment>

Parameters:

embeddings - A list of embeddings to be added to the store.

embedded - A list of original contents that were embedded.

Returns:

A list of auto-generated IDs associated with the added embeddings.

findRelevant

public List<EmbeddingMatch<TextSegment>> findRelevant(Embedding referenceEmbedding,
 int maxResults,
 double minScore)

Finds the most relevant (closest in space) embeddings to the provided reference embedding.

Specified by:

findRelevant in interface EmbeddingStore<TextSegment>

Parameters:

referenceEmbedding - The embedding used as a reference. Returned embeddings should be relevant (closest) to this one.

maxResults - The maximum number of embeddings to be returned.

minScore - The minimum relevance score, ranging from 0 to 1 (inclusive). Only embeddings with a score of this value or higher will be returned.

Returns:

A list of embedding matches. Each embedding match includes a relevance score (derivative of cosine distance), ranging from 0 (not relevant) to 1 (highly relevant).