Java JDBC模板的工作速度很慢

使用JDBCTemplate从数据库中获取行时出现性能问题。当我在plsql中运行sql时，我可以在3毫秒内得到结果，但代码中的同一查询在200毫秒左右工作。我认为它工作得很慢，因为在运行查询之前，创建了一个连接，我在其中浪费了太多时间。我想我需要一个连接池或smt。否则

在这里编写代码之前，我想谈谈我的spring boot项目的流程。客户端调用我的端点，在这个调用中，我使用来自多个表的多个查询。所有查询都运行缓慢，因为对于每个查询，都会创建另一个连接

数据库配置类 RestController中的查询 此功能最多需要2秒钟

刀 达伊姆普 解决方案 更改DriverManager数据源

@Configuration
public class DatabaseConfig {

    @Autowired
    private Environment env;

    @Autowired
    private DataSourceProperties dataSourceProperties;

    @Bean(name = "fraudDb")
    public DataSource masterDataSource() {
        DataSourceBuilder factory = DataSourceBuilder
                .create(this.dataSourceProperties.getClassLoader())
                .driverClassName(env.getProperty("driver-class-name"))
                .url(env.getProperty("fraud.url"))
                .username(env.getProperty("fraud.username"))
                .password(env.getProperty("fraud.password"));
        return factory.build();
    }

    @Bean(name = "ndvliveDb")
    public DataSource secondDataSource() {
        DataSourceBuilder factory = DataSourceBuilder
                .create(this.dataSourceProperties.getClassLoader())
                .driverClassName(env.getProperty("driver-class-name"))
                .url(env.getProperty("ndvlive.url"))
                .username(env.getProperty("ndvlive.username"))
                .password(env.getProperty("ndvlive.password"));
        return factory.build();
    }

    @Bean(name = "fraudJdbcTemplate")
    @Autowired
    public JdbcTemplate masterJdbcTemplate(@Qualifier("fraudDb") DataSource fraudDb) {
        return new JdbcTemplate(fraudDb);
    }

    @Bean(name = "ndvliveJdbcTemplate")
    @Autowired
    public JdbcTemplate secondaryJdbcTemplate(@Qualifier("ndvliveDb") DataSource ndvliveDb) {
        return new JdbcTemplate(ndvliveDb);
    }
}

---

您可以做几件事来提高性能：

不要使用

drivermanagedatasource

定义具有固定连接计数的连接池。要简化操作，请使用不会执行任何借用连接验证的

SingleConnectionDataSource

。这不是一个生产级设置，但在您的测试中将有较少的活动件

选择*而不是

，只指定所需的列。JDBC和命令行客户机之间解析
*
可能不同，最好删除这个未知的代码

将准备好的语句与

client\u no=？

一起使用，而不是将

client\u no=“+clientNo

连接起来。这将在检查不同的客户端编号时产生更好的查询计划缓存

---

请注意，JVM需要10000多次方法调用才能开始JIT编译和优化如果不预热JVM，代码会变慢。命令行客户端已编译为本机代码。

数据源和连接池。您能否解释HerediverManagerDataSource中的错误-因此没有连接池。每次创建和丢弃DB connection PreparedStatement时-而不是附加'clientNo''要查询，您可以使用PreparedStatement如果我使用除queryForObject之外的Prepared语句，我将获得更快的结果。我理解正确了吗？谢谢，现在我的查询很快：）正如您所说，我更改了所有查询。此外，我想我必须将DriverManager DataSoruce更改为DataSourceBuilder。+1此答案仅通过更改

driverManager数据源

至

SingleConnectionDataSource

。

private RbtranServiceInputModel services(FraudActionsRestRequest fraudActionsRestRequest) {
Long start = System.nanoTime();
        String debitSegmentId = ndvliveCustomerInfoService.getSBUCode(Integer.parseInt(cifNoSender));
        Long end = System.nanoTime();
        System.out.println("debitSegmentId " + (end - start) / 1e6);

        //10 ms - 20 ms
        start = System.nanoTime();
        String debitName = ndvliveCustomerInfoService.getNameSurname(new BigDecimal(cifNoSender), userId);
        end = System.nanoTime();
        System.out.println("debitName " + (end - start) / 1e6);

        //3 ms
        start = System.nanoTime();
        ResponseGetBMSInfo bmsInfo = ndvliveCustomerInfoService.getOnlineCustomerInfo(new BigDecimal(cifNoSender));
        end = System.nanoTime();
        System.out.println("bmsInfo " + (end - start) / 1e6);

        //10 MS
        start = System.nanoTime();
        Date passwordChangeDate = ndvliveCustomerInfoService.getPasswordChangeDate(new BigDecimal(cifNoSender), userId);
        end = System.nanoTime();
        System.out.println("passwordChangeDate " + (end - start) / 1e6);

        //10ms
        start = System.nanoTime();
        Date smartSmsGsmNoRegistrationDate = ndvliveCustomerInfoService.getSmartSmsGsmNoRegistrationDate(new BigDecimal(cifNoSender), userId);
        end = System.nanoTime();
        System.out.println("smartSmsGsmNoRegistrationDate " + (end - start) / 1e6);

        //6 ms
        start = System.nanoTime();
        Date membershipDate = ndvliveCustomerInfoService.getMembershipDate(new BigDecimal(cifNoSender), userId);
        end = System.nanoTime();
        System.out.println("membershipDate " + (end - start) / 1e6);

        start = System.nanoTime();
        BigDecimal smartSmsNo = ndvliveCustomerInfoService.getSmsGsmNo(new BigDecimal(cifNoSender));//TODO sms;
        end = System.nanoTime();
        System.out.println("smartSmsNo " + (end - start) / 1e6);

        start = System.nanoTime();
        String habitInfo = ndvliveCustomerInfoService.getHabitInfo(new BigDecimal(cifNoSender), channel);
        end = System.nanoTime();
        System.out.println("habitInfo " + (end - start) / 1e6);

        start = System.nanoTime();
        Date lastBlockSimDate = ndvliveCustomerInfoService.getLastBlockSimDate(new BigDecimal(cifNoSender), userId);
        end = System.nanoTime();
        System.out.println("lastBlockSimDate " + (end - start) / 1e6);

        start = System.nanoTime();
        boolean isFamiliar = ndvliveCustomerAccountInfoService.getFamiliarAccount(new BigDecimal(fraudActionsRestRequest.getDebitCustomerId()), fraudActionsRestRequest.getProcessCode(), fraudActionsRestRequest.getCreditAcctNumber(), fraudActionsRestRequest.getSmartSmsNo());
        end = System.nanoTime();
        System.out.println("isFamiliar " + (end - start) / 1e6);
        rbtranServiceInputModel.setKnownAccount(isFamiliar);

        start = System.nanoTime();
        boolean isInWhitelist = ndvliveDeviceInfoService.isInWhiteList(Long.parseLong(fraudActionsRestRequest.getDebitCustomerId()), fraudActionsRestRequest.getUserData02(), fraudActionsRestRequest.getDeviceId());
        end = System.nanoTime();
        System.out.println("isInWhitelist " + (end - start) / 1e6);
        rbtranServiceInputModel.setInWhitelist(isInWhitelist);
    }

public interface CustomerInformationTempDao {
    String getSbuCodeByClientNo(Integer clientNo);
}

@Repository
public class CustomerInformationTempDaoImpl implements CustomerInformationTempDao {

    @Autowired
    @Qualifier("ndvliveJdbcTemplate")
    private JdbcTemplate ndvliveJdbcTemplate;

    public String getSbuCodeByClientNo(Integer clientNo) {
        String query = "SELECT * FROM mytable WHERE client_no=" + clientNo;
        try {
            return ndvliveJdbcTemplate.queryForObject(query, (resultSet, i) -> resultSet.getString("SBU_CODE"));
        } catch (EmptyResultDataAccessException e) {
            return null;
        }
    }
}

@Configuration
public class DatabaseConfig {

    @Autowired
    private Environment env;

    @Autowired
    private DataSourceProperties dataSourceProperties;

    @Bean(name = "fraudDb")
    public DataSource masterDataSource() {
        DataSourceBuilder factory = DataSourceBuilder
                .create(this.dataSourceProperties.getClassLoader())
                .driverClassName(env.getProperty("driver-class-name"))
                .url(env.getProperty("fraud.url"))
                .username(env.getProperty("fraud.username"))
                .password(env.getProperty("fraud.password"));
        return factory.build();
    }

    @Bean(name = "ndvliveDb")
    public DataSource secondDataSource() {
        DataSourceBuilder factory = DataSourceBuilder
                .create(this.dataSourceProperties.getClassLoader())
                .driverClassName(env.getProperty("driver-class-name"))
                .url(env.getProperty("ndvlive.url"))
                .username(env.getProperty("ndvlive.username"))
                .password(env.getProperty("ndvlive.password"));
        return factory.build();
    }

    @Bean(name = "fraudJdbcTemplate")
    @Autowired
    public JdbcTemplate masterJdbcTemplate(@Qualifier("fraudDb") DataSource fraudDb) {
        return new JdbcTemplate(fraudDb);
    }

    @Bean(name = "ndvliveJdbcTemplate")
    @Autowired
    public JdbcTemplate secondaryJdbcTemplate(@Qualifier("ndvliveDb") DataSource ndvliveDb) {
        return new JdbcTemplate(ndvliveDb);
    }
}