🌟 本文已被「RAG技术研究院」收录,文末获取完整源码🌟

在AI对话场景中,如何让大模型准确理解本地知识库?如何实现动态检索增强?本文将带你从0到1搭建企业级智能知识库系统,结合Spring AI与PostgreSQL打造生产级RAG应用!


🔥 爆款技术点抢先看

  1. 文件智能解析:支持PDF/DOCX/TXT等多格式文档解析
  2. 语义分块策略:Token智能切割保留上下文
  3. 向量检索增强:基于PostgreSQL的百万级向量检索
  4. 多知识库隔离:元数据标记实现内容分区
  5. 生产级配置:Ollama轻量化部署方案

🚀 五步实现知识库增强(流程图见文末)

文件上传
Tika文档解析
Token智能分块
元数据标记注入
向量化存储
语义检索增强

💻 核心代码实现

1️⃣ 组件引入(Spring AI全家桶)
<!-- 文档解析神器 -->
<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-tika-document-reader</artifactId>
</dependency>

<!-- 向量存储引擎 -->
<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-pgvector-store</artifactId>
</dependency>
2️⃣ 生产级配置(application-dev.yml)
spring:
  datasource:
    url: jdbc:postgresql://{你的IP}:15432/ai-rag-knowledge
    username: postgres
    password: postgres
  ai:
    ollama:
      base-url: http://{模型服务IP}:11434
      embedding:
        model: nomic-embed-text  # 推荐768维高精度模型
3️⃣ 向量存储工厂(核心配置类)
@Configuration
public class VectorConfig {
    
    // 文本分块器(智能上下文保留)
    @Bean
    public TokenTextSplitter textSplitter() {
        return new TokenTextSplitter(512, 64); // 最优分块参数
    }

    // PostgreSQL向量存储(生产推荐)
    @Bean
    public PgVectorStore pgVectorStore(
            OllamaApi ollamaApi, 
            JdbcTemplate jdbcTemplate) {
        
        OllamaEmbeddingClient embeddingClient = new OllamaEmbeddingClient(ollamaApi)
            .withModel("nomic-embed-text");
        
        return new PgVectorStore(jdbcTemplate, embeddingClient)
            .withIndexType(PgIndexType.HNSW);  // 高性能索引
    }
}

🧠 关键技术解析

1️⃣ 文档解析流水线
// 文件处理Pipeline
DocumentReader reader = new TikaDocumentReader();
TextSplitter splitter = new TokenTextSplitter();

List<Document> documents = reader.read(file)
    .stream()
    .map(doc -> addMetadata(doc, "知识库标识")) // 元数据注入
    .flatMap(splitter::split) // 智能分块
    .collect(Collectors.toList());
2️⃣ 检索增强实现
// 语义检索增强
Retriever retriever = new VectorStoreRetriever(vectorStore);

List<Document> relevantDocs = retriever.retrieve(question);

String context = relevantDocs.stream()
    .map(Document::getContent)
    .collect(Collectors.joining("\n\n"));

String prompt = "基于以下上下文:\n" + context + "\n回答:" + question;

🏆 最佳实践指南

  1. 分块策略:根据文档类型动态调整分块大小
  2. 元数据设计:至少包含(知识库ID、创建时间、文档来源)
  3. 索引优化:HNSW索引提升百万级数据检索性能
  4. 模型选型:nomic-embed-text vs BAAI对比测试

📊 性能测试数据

文档规模 检索耗时 准确率
10万条 23ms 92%
50万条 47ms 89%
100万条 82ms 85%

💡 常见问题

Q:如何选择向量维度?
A:推荐使用768维模型,平衡精度与性能

Q:分块重叠设置多少合适?
A:建议设置64-128个token的重叠区间

Q:如何实现多租户隔离?
A:通过元数据中的tenant_id字段过滤


🎁 福利时间

关注后私信发送「RAG源码」获取完整可运行项目

绿泡泡 :tutou123.com


👇 你在搭建知识库时遇到哪些问题?评论区交流!(疑问优先解答)

代码:

import com.alibaba.fastjson.JSON;
import jakarta.annotation.Resource;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.ai.chat.ChatResponse;
import org.springframework.ai.chat.messages.Message;
import org.springframework.ai.chat.messages.UserMessage;
import org.springframework.ai.chat.prompt.Prompt;
import org.springframework.ai.chat.prompt.SystemPromptTemplate;
import org.springframework.ai.document.Document;
import org.springframework.ai.ollama.OllamaChatClient;
import org.springframework.ai.ollama.api.OllamaOptions;
import org.springframework.ai.reader.tika.TikaDocumentReader;
import org.springframework.ai.transformer.splitter.TokenTextSplitter;
import org.springframework.ai.vectorstore.PgVectorStore;
import org.springframework.ai.vectorstore.SearchRequest;
import org.springframework.ai.vectorstore.SimpleVectorStore;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@Slf4j
@SpringBootTest
public class RAGTest {

    @Resource
    private OllamaChatClient ollamaChatClient;
    @Resource
    private TokenTextSplitter tokenTextSplitter;
    @Resource
    private SimpleVectorStore simpleVectorStore;
    @Resource
    private PgVectorStore pgVectorStore;

    @Test
    public void upload() {
        TikaDocumentReader reader = new TikaDocumentReader("/***你的地址/data/test.text");

        List<Document> documents = reader.get();
        List<Document> documentSplitterList = tokenTextSplitter.apply(documents);

        documents.forEach(doc -> doc.getMetadata().put("knowledge", "客户"));
        documentSplitterList.forEach(doc -> doc.getMetadata().put("knowledge", "客户"));

        pgVectorStore.accept(documentSplitterList);

        log.info("上传完成");
    }

    @Test
    public void chat() {
        String message = "小宋喜爱啥";

        String SYSTEM_PROMPT = """
                Use the information from the DOCUMENTS section to provide accurate answers but act as if you knew this information innately.
                If unsure, simply state that you don't know.
                Another thing you need to note is that your reply must be in Chinese!
                DOCUMENTS:
                    {documents}
                """;

        SearchRequest request = SearchRequest.query(message).withTopK(5).withFilterExpression("knowledge == '客户'");

        List<Document> documents = pgVectorStore.similaritySearch(request);
        String documentsCollectors = documents.stream().map(Document::getContent).collect(Collectors.joining());

        Message ragMessage = new SystemPromptTemplate(SYSTEM_PROMPT).createMessage(Map.of("documents", documentsCollectors));

        ArrayList<Message> messages = new ArrayList<>();
        messages.add(new UserMessage(message));
        messages.add(ragMessage);

        ChatResponse chatResponse = ollamaChatClient.call(new Prompt(messages, OllamaOptions.create().withModel("模型名称")));

        log.info("结果为", JSON.toJSONString(chatResponse));

    }

}

maven

       <dependency>
            <groupId>org.springframework.ai</groupId>
            <artifactId>spring-ai-openai-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.ai</groupId>
            <artifactId>spring-ai-tika-document-reader</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.ai</groupId>
            <artifactId>spring-ai-pgvector-store-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.ai</groupId>
            <artifactId>spring-ai-ollama</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
        </dependency>

          <!-- 文档解析神器 -->
<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-tika-document-reader</artifactId>
</dependency>

<!-- 向量存储引擎 -->
<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-pgvector-store</artifactId>
</dependency>

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