检索器集成 - AI 开发中文文档

一个检索器是一个接口，它根据非结构化查询返回文档。它比向量存储更通用。检索器不需要能够存储文档，只需要能够返回（或检索）它们。检索器可以由向量存储创建，但也足够广泛，可以包含其他来源。检索器接受一个字符串查询作为输入，并返回一个 @[Document] 对象的列表作为输出。请注意，所有向量存储都可以转换为检索器。参考向量存储集成文档获取可用的向量存储。本页面列出了自定义检索器，通过继承 BaseRetriever 实现。

自带文档

以下检索器允许您索引和搜索自定义文档语料库。

检索器	自托管	云服务	包
`AmazonKnowledgeBasesRetriever`	❌	✅	`langchain-aws`
`ElasticsearchRetriever`	✅	✅	`langchain-elasticsearch`
`MongoDBAtlasHybridSearchRetriever`	❌	✅	`langchain-mongodb`
`MemstateRetriever`	❌	✅	`langchain-memstate`
`MengramRetriever`	✅	✅	`langchain-mengram`
`NVIDIARAGRetriever`	✅	❌	`langchain-nvidia-ai-endpoints`
`VertexAISearchRetriever`	❌	✅	`langchain-google-community`

外部索引

以下检索器将搜索外部索引（例如，由互联网数据或类似数据构建的）。

检索器	来源	包
`ApifySearchRetriever`	通过 Apify RAG Web 浏览器进行互联网搜索	`langchain-apify`
`DiffbotKnowledgeGraphRetriever`	在 Diffbot 知识图谱上进行实体搜索	`langchain-diffbot`
`DiffbotWebSearchRetriever`	通过 Diffbot 网络搜索 API 进行互联网搜索	`langchain-diffbot`
`ParallelSearchRetriever`	通过并行搜索 API 进行互联网搜索	`langchain-parallel`
`PerplexitySearchRetriever`	通过困惑度搜索 API 进行互联网搜索	`langchain-perplexity`
`YouRetriever`	互联网搜索	`langchain-youdotcom`

所有检索器

Retriever	Self-host	Cloud offering	Package
`Google drive`			`langchain-google-community`
`VertexAISearchRetriever`	❌	✅	`langchain-google-community`
`AmazonKnowledgeBasesRetriever`	❌	✅	`langchain-aws`
`MongoDBAtlas`			`langchain-mongodb`
`Cohere RAG`			`langchain-cohere`
`Cohere reranker`			`langchain-cohere`
`NVIDIARAGRetriever`	✅	❌	`langchain-nvidia-ai-endpoints`
`Pinecone rerank`			`langchain-pinecone`
`WatsonxRerank`			`langchain-ibm`
`PerplexitySearchRetriever`	❌	✅	`langchain-perplexity`
`Graph RAG`			`langchain-graph-retriever`
`ElasticsearchRetriever`	✅	✅	`langchain-elasticsearch`
`ParallelSearchRetriever`	❌	✅	`langchain-parallel`
`ApifySearchRetriever`			`langchain-apify`
`Self Querying with SAP HANA Cloud Vector Engine`			`langchain-hana`
`M3Retriever`	✅	❌	`m3-memory`
`SemanticaRetriever`	✅	❌	`semantica`
`Ragatouille`			`ragatouille`
`LLMSlimCompressor`	✅	❌	`llmslim`
`Nebius`			`langchain-nebius`
`LinkupSearchRetriever`			`langchain-linkup`
`Nimble Extract`			`langchain-nimble`
`Nimble Search`			`langchain-nimble`
`RecallRetriever`	✅	❌	`recall-rag`
`SingleStoreSQLDatabaseRetriever`	✅	✅	`langchain-singlestore`
`Sourcey`			`langchain-sourcey`
`SynapRetriever`			`maximem-synap-langchain`
`MachineLibraryRetriever`			`langchain-machinelibrary`
`YouRetriever`	❌	✅	`langchain-youdotcom`
`KapaRetriever`			`langchain-kapa-ai`
`ReplyLayerRetriever`	❌	✅	`langchain-replylayer`
`HydrafetchSearchRetriever`			`langchain-hydrafetch`
`Valyucontext`			`langchain-valyu`
`DiffbotKnowledgeGraphRetriever`			`langchain-diffbot`
`DiffbotWebSearchRetriever`			`langchain-diffbot`
`CKGRetriever`			`langchain-ckg`
`BlopusRetriever`			`langchain-blopus`
`RecallRetriever`	✅	✅	`langchain-recall`
`Contextual AI reranker`			`langchain-contextual`
`FoxNoseRetriever`	❌	✅	`langchain-foxnose`
`BoxRetriever`			`langchain-box`
`Dappier`			`langchain-dappier`
`YouTubeCommentsRetriever`			`langchain-youtube`
`YouTubePlaylistRetriever`			`langchain-youtube`
`YouTubeSearchRetriever`			`langchain-youtube`
`YouTubeTranscriptRetriever`			`langchain-youtube`
`YouTubeVideoRetriever`			`langchain-youtube`
`WhooshRetriever`	✅	❌	`langchain-whoosh`
`PolarisRetriever`			`langchain-polaris`
`AlfrescoRetriever`	✅	❌	`langchain-opendma`
`DocumentumRetriever`	✅	❌	`langchain-opendma`
`FileNetP8Retriever`	✅	❌	`langchain-opendma`
`OnBaseRetriever`	✅	❌	`langchain-opendma`
`OpenDMARetriever`	✅	❌	`langchain-opendma`
`MemstateRetriever`	❌	✅	`langchain-memstate`
`AlphaAINewsRetriever`			`langchain-alphai`
`AxioraRetriever`	❌	✅	`langchain-axiora`
`MengramRetriever`	✅	✅	`langchain-mengram`
`SpiceDB Retriever`			`langchain-spicedb`
`MembaseRetriever`		✅	`langchain-membase`
`SchemagateRetriever`			`langchain-schemagate`
`Kinetica vectorstore based retriever`			`langchain-kinetica`
`EgnyteRetriever`			`egnyte-langchain-connector`
`Permit`			`langchain-permit`
`HighSNRDocumentCompressor`	❌	✅	`langchain-highsnr`
`CoalentRetriever`	✅	❌	`langchain-coalent`
`HuggingBayRetriever`			`langchain-hugging-bay`
`Galaxia`			`langchain-galaxia-retriever`
`Cognee`			`langchain-cognee`
`StackOverflowAnswerRetriever`			`langchain-stackoverflow`
`StackOverflowSearchRetriever`			`langchain-stackoverflow`
`AgentMail`			`langchain-agentmail`
`DeweyRetriever`	❌	✅	`langchain-dewey`
`VectorizeRetriever`			`langchain-vectorize`
`arXiv`			`langchain-arxiv-retriever`
`IgptSearchRetriever`			`langchain-igpt`
`AlchemystMemory`	❌	✅	`alchemyst-langchain`
`RedditCommentsRetriever`			`langchain-reddit`
`RedditSearchRetriever`			`langchain-reddit`
`RedditSubredditRetriever`			`langchain-reddit`
`QuanticDataRetriever`			`langchain-quanticdata`
`HackerNewsCommentsRetriever`			`langchain-hackernews`
`HackerNewsFrontPageRetriever`			`langchain-hackernews`
`HackerNewsSearchRetriever`			`langchain-hackernews`
`PlayStoreAppRetriever`			`langchain-playstore`
`PlayStoreReviewsRetriever`			`langchain-playstore`
`Zotero`			`langchain-zotero-retriever`
`Greennode`			`langchain-greennode`
`EngramRetriever`			`langchain-engram`
`KeiroRetriever`	❌	✅	`langchain-keiro`
`IMAP`			`langchain-imap`
`Perigon`			`langchain-perigon`
`OpenMemoryRetriever`			`langchain-openmemory`