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Left Outer Join

Keep all rows from the left DataFrame, even without matches. Replace ___ with the correct code.

How it works: Replace the ___ blanks in the code editor with the correct PySpark code, then hit Run Code. Stuck? Try the Hint button.

Setup (read-only)

employees = spark.createDataFrame([
    (1, "Alice", 101),
    (2, "Bob", 102),
    (3, "Charlie", 999)  # No matching department!
], ["emp_id", "name", "dept_id"])

departments = spark.createDataFrame([
    (101, "Engineering"),
    (102, "Sales")
], ["dept_id", "dept_name"])

Your CodeCtrl/Cmd+Enter to run

Output

Output will appear here...