宣告：

因專案中使用clickhouse引擎這裡springboot使用的方式是jdbc方式連線，這種方式的好處是可以使用clickhouse 自帶的fetch方法批量從clickhouse中獲取資料，對於大量資料的下載來說，比較好

因為如果全部拿到記憶體中處理，大量資料會有記憶體溢位的結果

如果批量多次請求資料庫對於資料庫查詢等也不靠譜，所有直接使用clickhouse jdbc連線來滿足這種情況，不使用mybatis等框架來管理，這裡根據大家不同的需求酌情參考即可

使用方式：

第一步：加入clickhouse jar包依賴

 <!--clickhouse-->
        <dependency>
            <groupId>ru.yandex.clickhouse</groupId>
            <artifactId>clickhouse-jdbc</artifactId>
            <version>0.1.40</version>
        </dependency>
 

第二步：配置資料庫連線屬性配置檔案，yml方式 此處僅作為引數，不連線任何驅動

clickhouse:
  address: jdbc:clickhouse://172.20.xxx.xxx:8123
  username: default
  password: xxx
  db: marketing
  socketTimeout: 600000

第三步：新增資料庫連線操作util工具類

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import net.sf.json.JSONObject;
import ru.yandex.clickhouse.ClickHouseConnection;
import ru.yandex.clickhouse.ClickHouseDataSource;
import ru.yandex.clickhouse.settings.ClickHouseProperties;

import java.sql.*;
import java.util.*;

/**
 * @Description:
 * @Date 2018/11/12
 */
@Slf4j
@Component
public class ClickHouseUtil {

    private static String clickhouseAddress;

    private static String clickhouseUsername;

    private static String clickhousePassword;

    private static String clickhouseDB;

    private static Integer clickhouseSocketTimeout;

    @Value("${clickhouse.address}")
    public  void setClickhouseAddress(String address) {
        ClickHouseUtil.clickhouseAddress = address;
    }
    @Value("${clickhouse.username}")
    public  void setClickhouseUsername(String username) {
        ClickHouseUtil.clickhouseUsername = username;
    }
    @Value("${clickhouse.password}")
    public  void setClickhousePassword(String password) {
        ClickHouseUtil.clickhousePassword = password;
    }
    @Value("${clickhouse.db}")
    public  void setClickhouseDB(String db) {
        ClickHouseUtil.clickhouseDB = db;
    }
    @Value("${clickhouse.socketTimeout}")
    public  void setClickhouseSocketTimeout(Integer socketTimeout) {
        ClickHouseUtil.clickhouseSocketTimeout = socketTimeout;
    }


    public static Connection getConn() {

        ClickHouseConnection conn = null;
        ClickHouseProperties properties = new ClickHouseProperties();
        properties.setUser(clickhouseUsername);
        properties.setPassword(clickhousePassword);
        properties.setDatabase(clickhouseDB);
        properties.setSocketTimeout(clickhouseSocketTimeout);
        ClickHouseDataSource clickHouseDataSource = new ClickHouseDataSource(clickhouseAddress,properties);
        try {
            conn = clickHouseDataSource.getConnection();
            return conn;
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return null;
    }

    public static List<JSONObject> exeSql(String sql){
        log.info("cliockhouse 執行sql：" + sql);
        Connection connection = getConn();
        try {
            Statement statement = connection.createStatement();
            ResultSet results = statement.executeQuery(sql);
            ResultSetMetaData rsmd = results.getMetaData();
            List<JSONObject> list = new ArrayList();
            while(results.next()){
                JSONObject row = new JSONObject();
                for(int i = 1;i<=rsmd.getColumnCount();i++){
                    row.put(rsmd.getColumnName(i),results.getString(rsmd.getColumnName(i)));
                }
                list.add(row);
            }

            return list;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

}
 

第四步：Test簡單使用執行sql查詢資料

import com.renrenche.databus.common.ClickHouseUtil;
import com.renrenche.databus.common.Result;
import com.renrenche.databus.domain.logdata.fem.FemParam;
import com.renrenche.databus.service.fem.FemMainService;
import net.sf.json.JSONObject;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.List;

/**
 * @Auther: qixin
 * @Date: 2018/12/11 15:05
 * @Description:
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class SemTest {

    @Test
    public void getFrsDataTest(){
        System.out.println("******************");
        String sql="select * from marketing.sem_campaign_real_time_report";
        List<JSONObject> result= ClickHouseUtil.exeSql(sql);
        System.out.println("******************");
    }

}
 

執行完畢列印結果檢視即可，

fetch方法之後再補充

感謝觀看