Convert pyspark string to date format

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礼貌的吻别
礼貌的吻别 2020-11-22 05:21

I have a date pyspark dataframe with a string column in the format of MM-dd-yyyy and I am attempting to convert this into a date column.

I tried:

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  • 2020-11-22 05:58

    Update (1/10/2018):

    For Spark 2.2+ the best way to do this is probably using the to_date or to_timestamp functions, which both support the format argument. From the docs:

    >>> from pyspark.sql.functions import to_timestamp
    >>> df = spark.createDataFrame([('1997-02-28 10:30:00',)], ['t'])
    >>> df.select(to_timestamp(df.t, 'yyyy-MM-dd HH:mm:ss').alias('dt')).collect()
    [Row(dt=datetime.datetime(1997, 2, 28, 10, 30))]
    

    Original Answer (for Spark < 2.2)

    It is possible (preferrable?) to do this without a udf:

    from pyspark.sql.functions import unix_timestamp, from_unixtime
    
    df = spark.createDataFrame(
        [("11/25/1991",), ("11/24/1991",), ("11/30/1991",)], 
        ['date_str']
    )
    
    df2 = df.select(
        'date_str', 
        from_unixtime(unix_timestamp('date_str', 'MM/dd/yyy')).alias('date')
    )
    
    print(df2)
    #DataFrame[date_str: string, date: timestamp]
    
    df2.show(truncate=False)
    #+----------+-------------------+
    #|date_str  |date               |
    #+----------+-------------------+
    #|11/25/1991|1991-11-25 00:00:00|
    #|11/24/1991|1991-11-24 00:00:00|
    #|11/30/1991|1991-11-30 00:00:00|
    #+----------+-------------------+
    
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  • 2020-11-22 06:01

    The strptime() approach does not work for me. I get another cleaner solution, using cast:

    from pyspark.sql.types import DateType
    spark_df1 = spark_df.withColumn("record_date",spark_df['order_submitted_date'].cast(DateType()))
    #below is the result
    spark_df1.select('order_submitted_date','record_date').show(10,False)
    
    +---------------------+-----------+
    |order_submitted_date |record_date|
    +---------------------+-----------+
    |2015-08-19 12:54:16.0|2015-08-19 |
    |2016-04-14 13:55:50.0|2016-04-14 |
    |2013-10-11 18:23:36.0|2013-10-11 |
    |2015-08-19 20:18:55.0|2015-08-19 |
    |2015-08-20 12:07:40.0|2015-08-20 |
    |2013-10-11 21:24:12.0|2013-10-11 |
    |2013-10-11 23:29:28.0|2013-10-11 |
    |2015-08-20 16:59:35.0|2015-08-20 |
    |2015-08-20 17:32:03.0|2015-08-20 |
    |2016-04-13 16:56:21.0|2016-04-13 |
    
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  • 2020-11-22 06:07
    from datetime import datetime
    from pyspark.sql.functions import col, udf
    from pyspark.sql.types import DateType
    
    
    
    # Creation of a dummy dataframe:
    df1 = sqlContext.createDataFrame([("11/25/1991","11/24/1991","11/30/1991"), 
                                ("11/25/1391","11/24/1992","11/30/1992")], schema=['first', 'second', 'third'])
    
    # Setting an user define function:
    # This function converts the string cell into a date:
    func =  udf (lambda x: datetime.strptime(x, '%m/%d/%Y'), DateType())
    
    df = df1.withColumn('test', func(col('first')))
    
    df.show()
    
    df.printSchema()
    

    Here is the output:

    +----------+----------+----------+----------+
    |     first|    second|     third|      test|
    +----------+----------+----------+----------+
    |11/25/1991|11/24/1991|11/30/1991|1991-01-25|
    |11/25/1391|11/24/1992|11/30/1992|1391-01-17|
    +----------+----------+----------+----------+
    
    root
     |-- first: string (nullable = true)
     |-- second: string (nullable = true)
     |-- third: string (nullable = true)
     |-- test: date (nullable = true)
    
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  • Try this:

    df = spark.createDataFrame([('2018-07-27 10:30:00',)], ['Date_col'])
    df.select(from_unixtime(unix_timestamp(df.Date_col, 'yyyy-MM-dd HH:mm:ss')).alias('dt_col'))
    df.show()
    +-------------------+  
    |           Date_col|  
    +-------------------+  
    |2018-07-27 10:30:00|  
    +-------------------+  
    
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  • 2020-11-22 06:09

    possibly not so many answers so thinking to share my code which can help someone

    from pyspark.sql import SparkSession
    from pyspark.sql.functions import to_date
    
    spark = SparkSession.builder.appName("Python Spark SQL basic example")\
        .config("spark.some.config.option", "some-value").getOrCreate()
    
    
    df = spark.createDataFrame([('2019-06-22',)], ['t'])
    df1 = df.select(to_date(df.t, 'yyyy-MM-dd').alias('dt'))
    print df1
    print df1.show()
    

    output

    DataFrame[dt: date]
    +----------+
    |        dt|
    +----------+
    |2019-06-22|
    +----------+
    

    the above code to convert to date if you want to convert datetime then use to_timestamp. let me know if you have any doubt.

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  • 2020-11-22 06:15

    In the accepted answer's update you don't see the example for the to_date function, so another solution using it would be:

    from pyspark.sql import functions as F
    
    df = df.withColumn(
                'new_date',
                    F.to_date(
                        F.unix_timestamp('STRINGCOLUMN', 'MM-dd-yyyy').cast('timestamp')))
    
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