DATABRICKS-CERTIFIED-ASSOCIATE-DEVELOPER-FOR-APACHE-SPARK · Question #54
Which of the following code blocks returns a new DataFrame where column sqft from DataFrame storesDF has had its missing values replaced with the value 30,000? A sample of DataFrame storesDF is below:
The correct answer is E. storesDF.na.fill(30000, "sqft"). In PySpark, DataFrame.na.fill(value, subset) fills null/NaN values. The subset parameter accepts a string column name or a list of strings. Option E - storesDF.na.fill(30000, 'sqft') - correctly passes the fill value and the column name as a string. Option A uses Seq('sqft')…
Question
Which of the following code blocks returns a new DataFrame where column sqft from DataFrame storesDF has had its missing values replaced with the value 30,000? A sample of DataFrame storesDF is below:
Options
- AstoresDF.na.fill(30000, Seq("sqft"))
- BstoresDF.nafill(30000, col("sqft"))
- CstoresDF.na.fill(30000, col("sqft"))
- DstoresDF.fillna(30000, col("sqft"))
- EstoresDF.na.fill(30000, "sqft")
How the community answered
(25 responses)- B4% (1)
- C4% (1)
- E92% (23)
Explanation
In PySpark, DataFrame.na.fill(value, subset) fills null/NaN values. The subset parameter accepts a string column name or a list of strings. Option E - storesDF.na.fill(30000, 'sqft') - correctly passes the fill value and the column name as a string. Option A uses Seq('sqft'), which is Scala syntax (not valid in Python). Option B uses a non-existent method nafill. Option C passes a Column object col('sqft') as the subset, which is invalid - it must be a string or list of strings. Option D uses fillna (a valid alias) but also incorrectly passes a Column object rather than a string.
Topics
Community Discussion
No community discussion yet for this question.