大数据Spark “蘑菇云”行动补充内容第69课: Spark SQL案例之分析电影评分系统.
昨天的作业dataframe的 算子实现 :
import org.apache.spark.sql.types._
import org.apache.spark.sql.Row
val PATH = "/data/moviesData/"
val moviesData = sc.textFile(PATH + "movies.dat")
val ratingsData = sc.textFile(PATH + "ratings.dat")
val usersData = sc.textFile(PATH + "users.dat")
val userSchemaString = "USERID::GENDER::AGE"
val userSchema = StructType(userSchemaString.split("::").map(field => StructField(field, StringType, true)))
val userDataFrame = sqlContext.createDataFrame(usersData.map(_.split("::")).map(line => Row(line(0),line(1), line(2))), userS