mode (DataFrameWriter)

Specifies the behavior when data or table already exists.

Syntax

mode(saveMode)

Parameters

Parameter	Type	Description
saveMode	str	The save mode. Accepted values are 'append' (append to existing data), 'overwrite' (overwrite existing data), 'error' or 'errorifexists' (throw an exception if data exists), and 'ignore' (silently skip if data exists).

Returns

DataFrameWriter

Examples

Write a Parquet file back with various modes, and read it back.

Python

import tempfile
with tempfile.TemporaryDirectory(prefix="mode") as d:
    # Overwrite the path with a new Parquet file
    spark.createDataFrame(
        [{"age": 100, "name": "Alice"}]
    ).write.mode("overwrite").format("parquet").save(d)

    # Append another DataFrame into the Parquet file
    spark.createDataFrame(
        [{"age": 120, "name": "Sue"}]
    ).write.mode("append").format("parquet").save(d)

    # Read the Parquet file as a DataFrame.
    spark.read.parquet(d).show()
    # +---+-------------+
    # |age|         name|
    # +---+-------------+
    # |120| Sue          |
    # |100| Alice       |
    # +---+-------------+