Chat2DB：Spring AI MCP 直连数据库

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

<dependency>
    <groupId>org.springframework.experimental</groupId>
    <artifactId>spring-ai-mcp</artifactId>
    <version>0.4.1</version>
</dependency>

spring.ai.openai.chat.options.model=deepseek-chat
spring.ai.openai.base-url=https://api.deepseek.com
spring.ai.openai.api-key=sk-XXX

@Bean
public CommandLineRunner predefinedQuestions(ChatClient.Builder chatClientBuilder,
        List<McpFunctionCallback> functionCallbacks, ConfigurableApplicationContext context) {
    return args -> {
        var chatClient = chatClientBuilder
                .defaultFunctions(functionCallbacks.toArray(new McpFunctionCallback[0]))
                .build();
        String question1 = "你能链接我的postgres数据库，然后告诉我这个数据库有多少张表吗？";
        System.out.println("ASSISTANT: " + chatClient.prompt(question1).call().content());

        String question2 = "你能链接我的postgres数据库，然后告诉我这个商品表里面哪个车最贵吗？";
        System.out.println("ASSISTANT: " + chatClient.prompt(question2).call().content());
        context.close();
    };
}

@Bean
public List<McpFunctionCallback> functionCallbacks(McpSyncClient mcpClient) {
    return mcpClient.listTools(null)
            .tools()
            .stream()
            .map(tool -> new McpFunctionCallback(mcpClient, tool))
            .toList();
}

@Bean(destroyMethod = "close")
public McpSyncClient mcpClient() {
    var stdioParams = ServerParameters.builder("npx")
            .args("-y", "@modelcontextprotocol/server-postgres",
                  "postgresql://postgres:lengleng@localhost:5432")
            .build();

    var mcpClient = McpClient.using(new StdioClientTransport(stdioParams))
            .requestTimeout(Duration.ofSeconds(10)).sync();

    var init = mcpClient.initialize();
    System.out.println("MCP Initialized: " + init);
    return mcpClient;
}

-- 查询表数量
SELECT COUNT(*) as count FROM information_schema.tables 
WHERE table_schema = 'public';

-- 查询表结构
SELECT column_name, data_type 
FROM information_schema.columns 
WHERE table_name = 'products';

-- 查询商品数据
SELECT id, name, price 
FROM products 
ORDER BY price DESC;