Spark 2.2+
Spark 2.2 introduces typedLit
to support Seq
, Map
, and Tuples
(SPARK-19254) and following calls should be supported (Scala):
import org.apache.spark.sql.functions.typedLit
df.withColumn("some_array", typedLit(Seq(1, 2, 3)))
df.withColumn("some_struct", typedLit(("foo", 1, 0.3)))
df.withColumn("some_map", typedLit(Map("key1" -> 1, "key2" -> 2)))
Spark 1.3+ (lit
), 1.4+ (array
, struct
), 2.0+ (map
):
The second argument for DataFrame.withColumn
should be a Column
so you have to use a literal:
from pyspark.sql.functions import lit
df.withColumn('new_column', lit(10))
If you need complex columns you can build these using blocks like array
:
from pyspark.sql.functions import array, create_map, struct
df.withColumn("some_array", array(lit(1), lit(2), lit(3)))
df.withColumn("some_struct", struct(lit("foo"), lit(1), lit(.3)))
df.withColumn("some_map", create_map(lit("key1"), lit(1), lit("key2"), lit(2)))
Exactly the same methods can be used in Scala.
import org.apache.spark.sql.functions.{array, lit, map, struct}
df.withColumn("new_column", lit(10))
df.withColumn("map", map(lit("key1"), lit(1), lit("key2"), lit(2)))
To provide names for structs
use either alias
on each field:
df.withColumn(
"some_struct",
struct(lit("foo").alias("x"), lit(1).alias("y"), lit(0.3).alias("z"))
)
or cast
on the whole object
df.withColumn(
"some_struct",
struct(lit("foo"), lit(1), lit(0.3)).cast("struct<x: string, y: integer, z: double>")
)
It is also possible, although slower, to use an UDF.
Note:
The same constructs can be used to pass constant arguments to UDFs or SQL functions.