前提條件

• 已安裝Java環(huán)境，要求安裝JDK 1.8及以上版本。

• 已將客戶端IP地址添加至Lindorm白名單，具體操作請參見設置白名單。

• 已獲取云原生多模數(shù)據(jù)庫 Lindorm時序引擎的連接地址，具體操作請參見查看連接地址。

操作步驟

1. 通過以下兩種方式安裝Lindorm JDBC Driver依賴。

   • 手動安裝。

     在本地自行下載JAR包集成JDBC Driver，下載鏈接為：Lindorm-all-client。選擇需要安裝的版本，以2.1.5為例，下載lindorm-all-client-2.1.5.jar包。

   • 通過Maven下載。

     如果在Maven項目中集成JDBC Driver，創(chuàng)建Project并在pom.xml中添加以下依賴配置，具體內(nèi)容如下：

     <dependency>
         <groupId>com.aliyun.lindorm</groupId>  
         <artifactId>lindorm-all-client</artifactId>
         <version>2.2.1.3</version>
     </dependency>

     說明

     lindorm-all-client的版本號根據(jù)需求填寫。

2. 訪問Lindorm時序引擎。完整的代碼示例如下。

   import java.sql.*;
   
   class Test {
       public static void main(String[] args) {
           // 此處填寫Lindorm時序引擎JDBC連接地址
           String url = "jdbc:lindorm:tsdb:url=http://ld-bp12pt80qr38p****-proxy-tsdb-pub.lindorm.rds.aliyuncs.com:8242";
           Connection conn = null;
   
           try {
               conn = DriverManager.getConnection(url);
               try (Statement stmt = conn.createStatement()) {
                   //創(chuàng)建時序數(shù)據(jù)表，默認訪問 default database
                   stmt.execute("CREATE TABLE sensor1 (device_id VARCHAR TAG,region VARCHAR TAG,time TIMESTAMP,temperature DOUBLE,humidity DOUBLE,PRIMARY KEY(device_id))");
   
                   //批量寫入數(shù)據(jù)
                   stmt.addBatch("INSERT INTO sensor1(device_id, region, time, temperature, humidity) values('F07A1260','north-cn','2021-04-22 15:33:00',12.1,45)");
                   stmt.addBatch("INSERT INTO sensor1(device_id, region, time, temperature, humidity) values('F07A1260','north-cn','2021-04-22 15:33:10',13.2,47)");
                   stmt.addBatch("INSERT INTO sensor1(device_id, region, time, temperature, humidity) values('F07A1260','north-cn','2021-04-22 15:33:20',10.6,46)");
                   stmt.addBatch("INSERT INTO sensor1(device_id, region, time, temperature, humidity) values('F07A1261','south-cn','2021-04-22 15:33:00',18.1,44)");
                   stmt.addBatch("INSERT INTO sensor1(device_id, region, time, temperature, humidity) values('F07A1261','south-cn','2021-04-22 15:33:10',19.7,44)");
                   stmt.executeBatch();
                   stmt.clearBatch();
               }
   
               // 使用綁定參數(shù)的方式查詢數(shù)據(jù)
               // 強烈建議指定時間范圍減少數(shù)據(jù)掃描
               try (PreparedStatement pstmt = conn.prepareStatement("SELECT device_id, region,time,temperature,humidity FROM sensor1 WHERE time >= ? and time <= ?")) {
                   Timestamp startTime =Timestamp.valueOf("2021-04-22 15:33:00");
                   Timestamp endTime = Timestamp.valueOf("2021-04-22 15:33:20");
                   pstmt.setTimestamp(1, startTime);
                   pstmt.setTimestamp(2, endTime);
                   try (ResultSet rs = pstmt.executeQuery()) {
                       while (rs.next()) {
                           String device_id = rs.getString("device_id");
                           String region = rs.getString("region");
                           Timestamp time = rs.getTimestamp("time");
                           Double temperature = rs.getDouble("temperature");
                           Double humidity = rs.getDouble("humidity");
                           System.out.printf("%s %s %s %f %f\n", device_id, region, time, temperature, humidity);
                       }
                   }
               }
           } catch (SQLException e) {
               // 異常處理需要結(jié)合實際業(yè)務邏輯編寫
               e.printStackTrace();
           } finally {
               try {
                   if (conn != null) {
                       conn.close();
                   }
               } catch (SQLException e) {
                   e.printStackTrace();
               }
           }
       }
   }

   說明

   • JDBC連接地址相關參數(shù)說明，請參見JDBC連接地址說明。

   • JDBC Driver訪問時序引擎時支持的API接口和對應的方法請參見支持的API接口和方法。

   • Lindorm時序引擎支持的SQL語法請參見SQL語法參考。

   執(zhí)行成功預計返回以下結(jié)果：

   F07A1261 south-cn 2021-04-22 15:33:00.0 18.100000 44.000000
   F07A1261 south-cn 2021-04-22 15:33:10.0 19.700000 44.000000
   F07A1260 north-cn 2021-04-22 15:33:00.0 12.100000 45.000000
   F07A1260 north-cn 2021-04-22 15:33:10.0 13.200000 47.000000
   F07A1260 north-cn 2021-04-22 15:33:20.0 10.600000 46.000000