大数据SparkSql创建临时表并查询数据

import org.apache.spark.sql.{DataFrame, SparkSession}
import org.apache.spark.sql.types.{LongType, StringType, StructType}

/**
 * Author Vincer
 * Date 2019/09/26 10:10
 * Language Scala
 */
object StreamingDS {
    def main(args: Array[String]): Unit= {
        
        // 创建sparkSession
        val spark: SparkSession = SparkSession
            .builder()
            .master("local[*]")
            .appName("StreamingDS")
            .getOrCreate()
        // 导入隐式转换
        import spark.implicits._
        
        // 创建Schema
        val peopleSchema: StructType = new StructType()
            .add("name", StringType)
            .add("age", LongType)
            .add("sex", StringType)
        
        // 采集数据
        val peopleDF: DataFrame = spark.readStream
            .schema(peopleSchema)
            .json("E:\\tmp")
        
        // 创建临时表
        peopleDF.createOrReplaceTempView("user")
        // 查询数据
        spark.sql("select * from user where age > 20")
        
        // 数据输出
        peopleDF.writeStream
            .outputMode("append") //append模式输出
            .format("console") //打印到控制台
            .start()
            .awaitTermination()
        
    }
}