如果我在sparksql中使用hiveudf，它就可以工作了。如下所述。

val df=List(("$100", "$90", "$10")).toDF("selling_price", "market_price", "profit")
df.registerTempTable("test")
spark.sql("select default.encrypt(selling_price,'sales','','employee','id') from test").show

但是，以下操作不起作用。

//following is not working. not sure if you need to register a function for this 
val encDF = df.withColumn("encrypted", default.encrypt($"selling_price","sales","","employee","id"))
encDF.show

错误

error: not found: value default