即席查询
普通查询
Load Data
1) RDD DataFrame/Dataset
2) Local Cloud(HDFS/S3)
将数据加载成RDD
val masterLog = sc.textFile("file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-hadoop001.out")
val workerLog = sc.textFile("file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/logs/spark-hadoop-org.apache.spark.deploy.worker.Worker-1-hadoop001.out")
val allLog = sc.textFile("file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/logs/*out*")
masterLog.count
workerLog.count
allLog.count
存在的问题:使用使用SQL进行查询呢?
import org.apache.spark.sql.Row
val masterRDD = masterLog.map(x => Row(x))
import org.apache.spark.sql.types._
val schemaString = "line"
val fields = schemaString.split(" ").map(fieldName => StructField(fieldName, StringType, nullable = true))
val schema = StructType(fields)
val masterDF = spark.createDataFrame(masterRDD, schema)
masterDF.show
JSON/Parquet
val usersDF = spark.read.format("parquet").load("file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/examples/src/main/resources/users.parquet")
usersDF.show
spark.sql("select * from parquet.`file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/examples/src/main/resources/users.parquet`").show
Drill 大数据处理框架
从Cloud读取数据: HDFS/S3
val hdfsRDD = sc.textFile("hdfs://path/file")
val s3RDD = sc.textFile("s3a://bucket/object")
s3a/s3n
spark.read.format("text").load("hdfs://path/file")
spark.read.format("text").load("s3a://bucket/object")
val df=spark.read.format("json").load("file:///home/hadoop/app/spark-2.1.0-bin-2.6.0-cdh5.7.0/examples/src/main/resources/people.json")
df.show
TPC-DS
spark-packages.org