Skip to main content

chroma

换行符

Chroma（嵌入式的开源Apache 2.0数据库)

Chroma是一个开源的Apache 2.0嵌入式数据库。

设置​

  1. 在计算机上使用Docker运行Chroma 文档
  2. 安装Chroma JS SDK。
npm install -S chromadb

使用，索引和查询文档​

import { Chroma } from "langchain/vectorstores/chroma";
import { OpenAIEmbeddings } from "langchain/embeddings/openai";
import { TextLoader } from "langchain/document_loaders/fs/text";

// Create docs with a loader
const loader = new TextLoader("src/document_loaders/example_data/example.txt");
const docs = await loader.load();

// Create vector store and index the docs
const vectorStore = await Chroma.fromDocuments(docs, new OpenAIEmbeddings(), {
  collectionName: "a-test-collection",
});

// Search for the most similar document
const response = await vectorStore.similaritySearch("hello", 1);

console.log(response);
/*
[
  Document {
    pageContent: 'Foo\nBar\nBaz\n\n',
    metadata: { source: 'src/document_loaders/example_data/example.txt' }
  }
]
*/

使用，索引和查询文本​

import { Chroma } from "langchain/vectorstores/chroma";
import { OpenAIEmbeddings } from "langchain/embeddings/openai";

// text sample from Godel, Escher, Bach
const vectorStore = await Chroma.fromTexts(
  [
    `Tortoise: Labyrinth? Labyrinth? Could it Are we in the notorious Little
        Harmonic Labyrinth of the dreaded Majotaur?`,
    "Achilles: Yiikes! What is that?",
    `Tortoise: They say-although I person never believed it myself-that an I
        Majotaur has created a tiny labyrinth sits in a pit in the middle of
        it, waiting innocent victims to get lost in its fears complexity.
        Then, when they wander and dazed into the center, he laughs and
        laughs at them-so hard, that he laughs them to death!`,
    "Achilles: Oh, no!",
    "Tortoise: But it's only a myth. Courage, Achilles.",
  ],
  [{ id: 2 }, { id: 1 }, { id: 3 }],
  new OpenAIEmbeddings(),
  {
    collectionName: "godel-escher-bach",
  }
);

const response = await vectorStore.similaritySearch("scared", 2);

console.log(response);
/*
[
  Document { pageContent: 'Achilles: Oh, no!', metadata: {} },
  Document {
    pageContent: 'Achilles: Yiikes! What is that?',
    metadata: { id: 1 }
  }
]
*/

// You can also filter by metadata
const filteredResponse = await vectorStore.similaritySearch("scared", 2, {
  id: 1,
});

console.log(filteredResponse);
/*
[
  Document {
    pageContent: 'Achilles: Yiikes! What is that?',
    metadata: { id: 1 }
  }
]
*/

使用，从现有集合查询文档​

import { Chroma } from "langchain/vectorstores/chroma";
import { OpenAIEmbeddings } from "langchain/embeddings/openai";

const vectorStore = await Chroma.fromExistingCollection(
  new OpenAIEmbeddings(),
  { collectionName: "godel-escher-bach" }
);

const response = await vectorStore.similaritySearch("scared", 2);
console.log(response);
/*
[
  Document { pageContent: 'Achilles: Oh, no!', metadata: {} },
  Document {
    pageContent: 'Achilles: Yiikes! What is that?',
    metadata: { id: 1 }
  }
]
*/