Spark Scala UDF参数限制为10
我需要创建一个包含11个参数的Spark UDF。有什么办法可以做到吗? 我知道我们可以创建一个最多有10个参数的UDF 下面是10个参数的代码。它起作用了Spark Scala UDF参数限制为10,scala,apache-spark,apache-spark-sql,user-defined-functions,Scala,Apache Spark,Apache Spark Sql,User Defined Functions,我需要创建一个包含11个参数的Spark UDF。有什么办法可以做到吗? 我知道我们可以创建一个最多有10个参数的UDF 下面是10个参数的代码。它起作用了 val testFunc1 = (one: String, two: String, three: String, four: String, five: String, six: String, seven: String, eight: String, nine: String, ten: String
val testFunc1 = (one: String, two: String, three: String, four: String,
five: String, six: String, seven: String, eight: String, nine: String, ten: String) => {
if (isEmpty(four)) false
else four match {
case "RDIS" => three == "ST"
case "TTSC" => nine == "UT" && eight == "RR"
case _ => false
}
}
import org.apache.spark.sql.functions.udf
udf(testFunc1)
下面是11个参数的代码。面临未指定的值参数:数据类型问题
val testFunc2 = (one: String, two: String, three: String, four: String,
five: String, six: String, seven: String, eight: String, nine: String, ten: String, ELEVEN: String) => {
if (isEmpty(four)) false
else four match {
case "RDIS" => three == "ST"
case "TTSC" => nine == "UT" && eight == "RR" && ELEVEN == "OR"
case _ => false
}
}
import org.apache.spark.sql.functions.udf
udf(testFunc2) // compilation error
您可以创建一个新列,它是一个列数组:
df.withColumns("arrCol", array("col1", "col2", "col3", ...)
现在,您可以对数组执行UDF
val testFunc(vals: Seq[String]): String = ...
我建议将参数打包到地图中:
“map litone,$1,littwo,$1”是如何工作的?它应该是类似于'map litone->$one,littwo->$one`@raam是的,key,value,key,value等等,然后我们可以写'df.withColumnudf\u result,myUDFmaplitone,$one,littwo,$one.show',而不是另外一个withcolumn这正是我的建议!谢谢你花时间写下答案+1@SiddaramH映射不需要导入
import org.apache.spark.sql.functions._
val df = sc.parallelize(Seq(("a","b"),("c","d"),("e","f"))).toDF("one","two")
val myUDF = udf((input:Map[String,String]) => {
// do something with the input
input("one")=="a"
})
df
.withColumn("udf_args",map(
lit("one"),$"one",
lit("two"),$"one"
)
)
.withColumn("udf_result", myUDF($"udf_args"))
.show()
+---+---+--------------------+----------+
|one|two| udf_args|udf_result|
+---+---+--------------------+----------+
| a| b|Map(one -> a, two...| true|
| c| d|Map(one -> c, two...| false|
| e| f|Map(one -> e, two...| false|
+---+---+--------------------+----------+