日期函数：current_date、current_timestamp
数学函数：round
随机函数：rand
字符串函数：concat、concat_ws
自定义udf和udaf函数
文档地址：http://spark.apache.org/docs/latest/api/scala/index.html#org.apache.spark.sql.functions$
代码
object OtherFunction {
def main(args: Array[String]) {
val sparkSession = SparkSession
.builder()
.appName("OtherFunction")
.master("local")
.getOrCreate()
import sparkSession.implicits._
import org.apache.spark.sql.functions._
val employeePath = this.getClass.getClassLoader.getResource("employee.json").getPath
val departmentPath = this.getClass.getClassLoader.getResource("department.json").getPath
val employeeDF = sparkSession.read.json(employeePath)
val departmentDF = sparkSession.read.json(departmentPath)
val employeeDS = employeeDF.as[Employee]
val departmentDS = departmentDF.as[Department]
employeeDS
.select(employeeDS("name"), current_date(), current_timestamp(), rand(), round(employeeDS("salary"), 2), concat(employeeDS("gender"), employeeDS("age")), concat_ws("|", employeeDS("gender"), employeeDS("age")))
.show()
}
}
