Nóta
Teastaíonn údarú chun rochtain a fháil ar an leathanach seo. Is féidir leat triail a bhaint as shíniú isteach nó eolairí a athrú.
Teastaíonn údarú chun rochtain a fháil ar an leathanach seo. Is féidir leat triail a bhaint as eolairí a athrú.
Returns col2 if col1 is null, or col1 otherwise.
For the corresponding Databricks SQL function, see ifnull function.
Syntax
from pyspark.sql import functions as dbf
dbf.ifnull(col1=<col1>, col2=<col2>)
Parameters
| Parameter | Type | Description |
|---|---|---|
col1 |
pyspark.sql.Column or str |
The first column to check. |
col2 |
pyspark.sql.Column or str |
The value to return if col1 is null. |
Examples
from pyspark.sql import functions as dbf
df = spark.createDataFrame([(None,), (1,)], ["e"])
df.select(dbf.ifnull(df.e, dbf.lit(8))).show()
+------------+
|ifnull(e, 8)|
+------------+
| 8|
| 1|
+------------+