Column.
asc_nulls_first
Returns a sort expression based on ascending order of the column, and null values return before non-null values.
New in version 2.4.0.
Examples
>>> from pyspark.sql import Row >>> df = spark.createDataFrame([('Tom', 80), (None, 60), ('Alice', None)], ["name", "height"]) >>> df.select(df.name).orderBy(df.name.asc_nulls_first()).collect() [Row(name=None), Row(name='Alice'), Row(name='Tom')]