FlinkTableAPI和FlinkSql将计算出来的结果写到文件里面去-CFANZ编程社区

sensor.txt

sensor_1,1547718199,35.8
sensor_6,1547718201,15.4
sensor_7,1547718202,6.7
sensor_10,1547718205,38.1
sensor_1,1547718207,37.2
sensor_1,1547718212,33.5
sensor_1,1547718215,38.1

TableAPI

import org.apache.flink.streaming.api.scala._
import org.apache.flink.table.api.{DataTypes, EnvironmentSettings, Table}
import org.apache.flink.table.api.scala._
import org.apache.flink.table.descriptors.{Csv, FileSystem, Schema}


// 输出表计算的结果到文件
object OutputTableTest {
  def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    env.setParallelism(1)

    // 读取数据创建DataStream
    val inputStream: DataStream[String] = env.
      readTextFile("D:\\20-Flink\\FlinkTutorial\\src\\main\\resources\\sensor.txt")
    val dataStream: DataStream[SensorReading] = inputStream
      .map(data => {
        val dataArray = data.split(",")
        SensorReading(dataArray(0), dataArray(1).toLong, dataArray(2).toDouble)
      })

    // 创建表环境
    val tableEnv: StreamTableEnvironment = StreamTableEnvironment.create(env)

    // 将DataStream转换成Table
    // 你可以给表字段换个顺序,或者as个别名
    val sensorTable: Table = tableEnv.fromDataStream(dataStream, 'id, 'temperature as 'temp, 'timestamp as 'ts)
    // 对Table进行转换操作，得到结果表
    val resultTable: Table = sensorTable
      .select('id, 'temp)
      .filter('id === "sensor_1")

    //    val aggResultTable: Table = sensorTable
    //      .groupBy('id)
    //      .select('id, 'id.count as 'count)

    // 定义一张输出表，这就是要写入数据的TableSink
    tableEnv.connect(new FileSystem().
      path("D:\\20-Flink\\FlinkTutorial\\src\\main\\resources\\out2.txt"))
      .withFormat(new Csv())
      .withSchema(new Schema()
        .field("id", DataTypes.STRING())
        .field("temp", DataTypes.DOUBLE())  // 注意定义的字段和输出的数据要一一对应
      )
      .createTemporaryTable("outputTable")

    // 将结果表写入table sink
    resultTable.insertInto("outputTable")

    env.execute("output table test")
  }
}

输出文件结果

out2.txt

sensor_1,35.8
sensor_1,37.2
sensor_1,33.5
sensor_1,38.1

FlinkSql 方式

import org.apache.flink.streaming.api.scala._
import org.apache.flink.table.api.{DataTypes, EnvironmentSettings, Table}
import org.apache.flink.table.api.scala._
import org.apache.flink.table.descriptors.{Csv, FileSystem, Schema}


// 输出表计算的结果到文件
object OutputTableTest {
  def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    env.setParallelism(1)

    // 读取数据创建DataStream
    val inputStream: DataStream[String] = env.
      readTextFile("D:\\20-Flink\\FlinkTutorial\\src\\main\\resources\\sensor.txt")
    val dataStream: DataStream[SensorReading] = inputStream
      .map(data => {
        val dataArray = data.split(",")
        SensorReading(dataArray(0), dataArray(1).toLong, dataArray(2).toDouble)
      })

    // 创建表环境
    val tableEnv: StreamTableEnvironment = StreamTableEnvironment.create(env)

    // 将DataStream转换成Table
    // 你可以给表字段换个顺序,或者as个别名
    val sensorTable: Table = tableEnv.fromDataStream(dataStream, 'id, 'temperature as 'temp, 'timestamp as 'ts)
    // 对Table进行转换操作，得到结果表

    val resultTable: Table = tableEnv.
      sqlQuery("select id, temp from "+sensorTable+" where id  = 'sensor_1' ")

    // 定义一张输出表，这就是要写入数据的TableSink
    tableEnv.connect(new FileSystem().
      path("D:\\20-Flink\\FlinkTutorial\\src\\main\\resources\\out3.txt"))
      .withFormat(new Csv())
      .withSchema(new Schema()
        .field("id", DataTypes.STRING())
        .field("temp", DataTypes.DOUBLE()) // 注意定义的字段和输出的数据要一一对应
      )
      .createTemporaryTable("outputTable")

    // 将结果表写入table sink
    resultTable.insertInto("outputTable")

    env.execute("output table test")
  }
}

输出文件结果

out3.txt

sensor_1,35.8
sensor_1,37.2
sensor_1,33.5
sensor_1,38.1