desc_nulls_first (列)

按降序对列进行排序,并首先显示 null 值。

Syntax

desc_nulls_first()

退货

示例

from pyspark.sql import Row
df = spark.createDataFrame(
    [('Tom', 80), (None, 60), ('Alice', None)], ["name", "height"])
df.select(df.name).orderBy(df.name.desc_nulls_first()).collect()
# [Row(name=None), Row(name='Tom'), Row(name='Alice')]