// 首先定义StudentGrade类 case class StudentGrade(name: String, subject: String, grade: Long) // 生成DataFrame val dfSG = spark.read.json("data/examples/target/scala-2.11/classes/student_grade.json") // 方法1:通过map函数手动转换为Dataset[StudentGrade]类型 val dsSG: Dataset[StudentGrade] = ...
name.stringpubID ="";// Open the connection and read data into the DataReader.connection.Open(); SqlDataReader reader = command.ExecuteReader(CommandBehavior.SequentialAccess);while(reader.Read()) {// Get the publisher id, which must occur before getting the logo.pubID = reader.GetString(0)...