fill (DataFrameNaFunctions) s

Returns a new DataFrame in which null values are filled with a new value. DataFrame.fillna and DataFrameNaFunctions.fill are aliases of each other.

Syntax

fill(value, subset=None)

Parameters

Parameter	Type	Description
value	int, float, str, bool, or dict	The value to replace null values with. If a dict is provided, subset is ignored and value must be a mapping from column name to replacement value. Replacement values must be int, float, bool, or str.
subset	str, tuple, or list, optional	Column names to consider. Columns in subset that do not have a matching data type for value are ignored.

Returns

DataFrame

Examples

df = spark.createDataFrame([
    (10, 80.5, "Alice", None),
    (5, None, "Bob", None),
    (None, None, "Tom", None),
    (None, None, None, True)],
    schema=["age", "height", "name", "bool"])

Fill all null values with 50 for numeric columns.

df.na.fill(50).show()
# +---+------+-----+----+
# |age|height| name|bool|
# +---+------+-----+----+
# | 10|  80.5|Alice|NULL|
# |  5|  50.0|  Bob|NULL|
# | 50|  50.0|  Tom|NULL|
# | 50|  50.0| NULL|true|
# +---+------+-----+----+

Fill all null values with False for boolean columns.

df.na.fill(False).show()
# +----+------+-----+-----+
# | age|height| name| bool|
# +----+------+-----+-----+
# |  10|  80.5|Alice|false|
# |   5|  NULL|  Bob|false|
# |NULL|  NULL|  Tom|false|
# |NULL|  NULL| NULL| true|
# +----+------+-----+-----+

Fill null values with 50 for age and "unknown" for name.

df.na.fill({'age': 50, 'name': 'unknown'}).show()
# +---+------+-------+----+
# |age|height|   name|bool|
# +---+------+-------+----+
# | 10|  80.5|  Alice|NULL|
# |  5|  NULL|    Bob|NULL|
# | 50|  NULL|    Tom|NULL|
# | 50|  NULL|unknown|true|
# +---+------+-------+----+

Fill all null values with "Spark" for the name column.

df.na.fill(value='Spark', subset='name').show()
# +----+------+-----+----+
# | age|height| name|bool|
# +----+------+-----+----+
# |  10|  80.5|Alice|NULL|
# |   5|  NULL|  Bob|NULL|
# |NULL|  NULL|  Tom|NULL|
# |NULL|  NULL|Spark|true|
# +----+------+-----+----+