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Comment: Published by Scroll Versions from space DEV and version r083

D toc

Excerpt

Formats a specified Datetime set of values according to the specified date format. Source values can be a reference to a column containing Datetime values.

  • If the source Datetime value does not include a valid input for this function, a missing value is returned.
  • D s product
    rtrue
    supports a wide variety of formats for Datetime fields. For more information on supported date formats, see Datetime Data Type.
  • You can explore the available Datetime formats through the Transformer page. From a column's type drop-down, select Date/Time . Then, select the formatting category. From the displayed drop-down, you can select a specific format. When this transform step is added to your recipe, you can edit it to see how the format is specified in
    D s lang
    .

For more information on formatting numeric types, see NUMFORMAT Function.

D s lang vs sql

D s
snippetBasic

D lang syntax
RawWrangletrue
Typeref
showNotetrue
WrangleTextderive type:single value: dateformat(MyDate, 'yyyy-MM-dd') as: 'dateformat_MyDate'

dateformat(MyDate, 'yyyy-MM-dd')


Output:
Returns the valid date values in the MyDate column converted to year-month-day format.

D s
snippetSyntax

D lang syntax
RawWrangletrue
Typesyntax
showNotetrue
WrangleTextderive type:single value:dateformat(Datetime_col, date_format_string)

dateformat(Datetime_col, date_format_string)


ArgumentRequired?Data TypeDescription
Datetime_colYdatetimeName of column containing date values to be formatted
date_format_stringYstringString literal identifying the date format to apply to the value

D s lang notes

datetime_col

Name of the column whose date data is to be formatted.

  • Missing values for this function in the source data result in missing values in the output.
  • Multiple columns and wildcards are not supported.

D s
snippetusage

 

Required?Data TypeExample Value
YesDatetimemyDate

date_format_string

String value indicating the date format to apply to the input values.

D s product
supports Java formatting strings, with some exceptions.

Info

NOTE: If the platform cannot recognize the date format string, the generated result is written as a string value.

For more information on supported date formats, see Datetime Data Type.

  • Missing values for this function in the source data result in missing values in the output.
  • Multiple columns and wildcards are not supported.

D s
snippetusage

Required?Data TypeExample Value
YesString'MM/dd/yyyy'

D s
snippetExamples

Example - formatting date values

This example illustrates several ways of wrangling heterogeneous date values, including the use of the DATEFORMAT function.

Source:

Your dataset includes the following messy date values:

MyDate
2/1/00 9:20
4/5/10 11:25
6/7/99 22:00
12/20/1894 15:45:00
13/7/1999 22:00:00

Transformation:

When this data is loaded into the application, it is not immediately recognized as a Datetime column, as the variation among the data complicates deciding on the proper date format. The first three rows look to be in a consistent format, but the other two are problematic.

You can try to change the column to a Datetime type with a format that matches the first three rows. You can select the appropriate format through the type drop-down. When previewed, the transform looks like the following:

Info

NOTE: Do not add this transform at this time. It is strictly used for reviewing the effects on data quality.

D trans
RawWrangletrue
p03Value'mm-dd-yy hh:mm:ss','mm*dd*yy*HH:MM'
Typestep
WrangleTextsettype col: MyDate type: 'Datetime','mm-dd-yy hh:mm:ss','mm*dd*yy*HH:MM'
p01NameColumns
p01ValueMyDate
p02NameNew type
p02ValueCustom or Date/Time
p03NameSpecify type
SearchTermChange column data type

When the column is reformatted, you should notice that the last two values in the column are mismatched. In the column histogram, you can see that date ranges include the 1999 date in the third row, so the final row should work if it was a valid date.

The 1894 value looks like an outlier value and could be removed:

D trans
RawWrangletrue
p03Valuematches([MyDate], `12/20/1894`)
Typestep
WrangleTextdelete row: matches([MyDate], `12/20/1894`)
p01NameCondition
p01ValueCustom formula
p02NameType of formula
p02ValueCustom single
p03NameCondition
p04ValueDelete matching rows
p04NameAction
SearchTermFilter rows

For the remaining 1999 row, you can delete it or use the following transforms to conform it to the other rows. Use the following transform to change the 13 month value to a 12:

D trans
RawWrangletrue
p03Value'12\/'
Typestep
WrangleTextreplace col: MyDate on: `13/` with: '12\/' global: true
p01NameColumn
p01ValueMyDate
p02NameFind
p02Value`13/`
p03NameReplace with
p04Valuetrue
p04NameMatch all occurrences
SearchTermReplace text or pattern

The following two transforms complete the cleanup steps:

D trans
RawWrangletrue
p03Value'\/99'
Typestep
WrangleTextreplace col: MyDate on: `/1999` with: '\/99' global: true
p01NameColumn
p01ValueMyDate
p02NameFind
p02Value`/1999`
p03NameReplace with
p04Valuetrue
p04NameMatch all occurrences
SearchTermReplace text or pattern

D trans
RawWrangletrue
p03Value':00'
Typestep
WrangleTextreplace col: MyDate on: `:#+:00` with: ':00' global: true
p01NameColumn
p01ValueMyDate
p02NameFind
p02Value`:#+:00`
p03NameReplace with
p04Valuetrue
p04NameMatch all occurrences
SearchTermReplace text or pattern

If you apply the original formatting step, all dates are valid:

D trans
RawWrangletrue
p03Value'mm-dd-yy hh:mm:ss','mm*dd*yy*HH:MM'
Typestep
WrangleTextsettype col: MyDate type: 'Datetime','mm-dd-yy hh:mm:ss','mm*dd*yy*HH:MM'
p01NameColumns
p01ValueMyDate
p02NameNew type
p02ValueCustom or Date/Time
p03NameSpecify type
SearchTermChange column data type

Now, your Datetime column can be formatted as needed using the dateformat function. The following step generates a new column that contains year, month, and day information as a single numeric value:

D trans
RawWrangletrue
Typestep
WrangleTextderive type:single value:dateformat(MyDate, 'yyyyMMdd')
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(MyDate, 'yyyyMMdd')
SearchTermNew formula

Results:

The final dataset should look like the following:

MyDatedateformat_MyDate
2/1/00 9:2020000201
4/5/10 11:2520100405
6/7/99 22:0019990607
12/7/99 22:0019991207

Example - Other date formatting variations

Numeric date, year first

SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'yyyy-MM-dd') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'yyyy-MM-dd')
p03NameNew column name
SearchTermNew formula

2016-02-15

1999-03-12

2011-11-21

Numeric date, American style

SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'M/d/yy') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'M/d/yy')
p03NameNew column name
SearchTermNew formula

2/15/16

3/12/99

11/21/11

Full written date

SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'MMMM dd, yyyy') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'MMMM dd, yyyy')
p03NameNew column name
SearchTermNew formula

February 15, 2016

March 12, 1999

November 21, 2011

Abbreviated date, including abbreviated day of week

SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'EEE MMM dd, yyyy') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'EEE MMM dd, yyyy')
p03NameNew column name
SearchTermNew formula

Mon Feb 15, 2016

Fri Mar 12, 1999

Mon Nov 21, 2011

Full 24-hour time

SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'HH:mm:ss.SSS') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'HH:mm:ss.SSS')
p03NameNew column name
SearchTermNew formula

13:26:58.123

2:45:21.456

23:02:18.000

Twelve-hour time with AM/PM indicator


SourceTransformationResults

2/15/16 13:26:58.123

3/12/99 2:45:21.456

11/21/11 23:02:18.000

D trans
RawWrangletrue
p03Value'newTimestamp'
Typestep
WrangleTextderive type:single value:dateformat(Timestamp,'h:mm:ss a') as:'newTimestamp'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuedateformat(Timestamp,'h:mm:ss a')
p03NameNew column name
SearchTermNew formula

Info

NOTE: For this function, use of the lower-case hour indicator (h or hh) requires the use of an AM/PM indicator (a).

 

 

1:26:58 PM

2:45:21 AM

11:02:18 PM

For more information on supported date formats, see Datetime Data Type.

D s also
labeldate