Spark dataframe orderBy using a variable

Question

I am trying to do something like this, but it gives an error. What is the right way of doing so while still using a variable?

import org.apache.spark.sql._
....
val seq = Seq[Column](new Column("colX"), new Column("colY"), new Column("colZ"))
someDataFrame.orderBy(seq)

I know that one can also use something like orderBy("colX", "colY", "colZ") , but here I want to use a variable because my order sequence would change on different conditions.

I get an error like this.

error: overloaded method value orderBy with alternatives:
  (sortExprs: org.apache.spark.sql.Column*)org.apache.spark.sql.Dataset[org.apache.spark.sql.Row] <and>
  (sortCol: String,sortCols: String*)org.apache.spark.sql.Dataset[org.apache.spark.sql.Row]
 cannot be applied to (Seq[org.apache.spark.sql.Column])

Answer 1

Try this, you should convert your Array or List to a sequence of values (an actual sequence not a Seq )

someDataFrame.orderBy(seq:_*)

Quick test here:

INPUT

df.show
+---+---+
| _1| _2|
+---+---+
|  c|  0|
|  b|  1|
|  a|  0|
+---+---+


val s = Seq(new Column("_1"), new Column("_2"))

df.orderBy(s:_*).show
+---+---+
| _1| _2|
+---+---+
|  a|  0|
|  b|  1|
|  c|  0|
+---+---+