PARSEDATE Function
Evaluates an input against the default input formats or (if specified) an array of Datetime format strings in their listed order. If the input matches one of the formats, the function outputs a Datetime value.
Inputs can be of any type.
If the input is not a Datetime value and does match one of the specified formats, the output is in the following format:
yyyy-MM-dd HH:mm:ss.If the input is a Datetime value and does match, the output is in the input's Datetime format.
Nota
Parsing of dates may depend on how dates are recognized by the running environment where the transformation is executed. In some cases, locale settings for the backend running environment may be different from your user locale settings, which affect how values are interpreted in the Transformer page. If you are having difficulties with execution of the PARSEDATE function, you can try to set your locale settings to U.S. to fix your recipes. This is a known issue.
After you have converted your strings values to dates, if a sufficient percentage of input strings from a column are successfully converted to one of the matching formats, the column may be retyped as Datetime.
Designer Cloud supports a wide variety of formats for Datetime fields.
You can explore the available Datetime formats through the Transformer page. From a column's type drop-down, selectDate/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 Wrangle.
You can then use the DATEFORMAT function to convert the output values to your preferred Datetime format. See DATEFORMAT Function.
Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.
Basic Usage
parsedate(strDate, ['yyyy-MM-dd','yyyy-MM','yyyy/MM','yyyy-MM-dd'])
Output: Returns a value structured in yyyy-MM-dd HH:mm:ss format if the input value in strDate matches any of default formats, which are the following:
'yyyy-MM-dd HH:mm:ss' 'yyyy/MM/dd HH:mm:ss' 'yyyy-MM-dd' 'yyyy/MM/dd'
parsedate(strDate, ['yyyy-MM','yyyy/MM',])
Output: Returns a value structured in yyyy-MM-dd HH:mm:ss format if the input value in strDate matches any of the listed formats for dates.
Syntax and Arguments
parsedate(date_col, date_formats_array)
Argument | Required? | Data Type | Description |
|---|---|---|---|
date_col | Y | any | Literal, name of a column, or a function returning values to match |
date_formats_array | N | string | (optional) An array of date format strings that are used to match against input values. |
For more information on syntax standards, see Language Documentation Syntax Notes.
date_col
Literal, column name, or function returning values that are to be evaluated for conversion to Datetime values.
Inputs values can be of any type.
Missing values for this function in the source data result in null values in the output.
Multiple columns and wildcards are not supported.
Usage Notes:
Required? | Data Type | Example Value |
|---|---|---|
Yes | any | 'February 24, 2019' |
date_formats_array
Array of String values of the date formats to evaluate the inputs.
When a non-Datetime input value matches one of the date formats in the array, the output is the input value converted to the following format:
yyyy-MM-dd HH:mm:ss
Datetime inputs are outputted in their source format.
Designer Cloud supports Java formatting strings, with some exceptions.
Nota
If the platform cannot recognize the date format string, a null value is written as the output.
Usage Notes:
Required? | Data Type | Example Value |
|---|---|---|
No | Array of Strings | ['yyyy-MM','yyyy/MM'] |
Examples
Suggerimento
For additional examples, see Common Tasks.
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:
MyDateStrings |
|---|
2/1/00 14:20 |
4/5/10 11:25 |
6/7/99 22:00 |
13/7/1999 22:00 |
12-20-1894 15:45:00 |
08-12-1956 22:01:04 |
Transformation:
To enable easier comparison in the data grid, you choose to create a new column with the parsed values. From the above, you identify two date formats:
'MM/dd/yy hh:mm' 'MM/dd/YYYY hh:mm:ss'
Nota
Since only one of the above formats matches the default formats, you must specify both in the transformation to perform the proper evalation.
You create the following transformation to parse them:
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | parsedate(myDateStrings, ['MM/dd/yy hh:mm','MM/dd/YYYY hh:mm:ss']) |
Parameter: New column name | 'myParsedDates' |
When the above step is added to the recipe, the output is as follows:
MyDateStrings | myParsedDates |
|---|---|
2/1/00 14:20 | 2000-02-01 14:20:00 |
4/5/10 11:25 | 2010-04-05 11:25:00 |
6/7/99 22:00 | 1999-06-07 22:00:00 |
13/7/1999 22:00 | 13/7/1999 22:00 |
12-20-1894 15:45:00 | 1894-12-20 15:45:00 |
08-12-1956 22:01:04 | 1956-08-12 22:01:04 |
The output myParsedDates column is retyped as a Datetime column with one mismatched value: 3/7/1999 22:00.
This value does not match any of our date formats specified in the array. The solution is to modify the recipe step to include the appropriate format as part of the array:
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | parsedate(myDateStrings, ['MM/dd/yy hh:mm','MM/dd/YYYY hh:mm:ss','dd/MM/yyyy hh:mm']) |
Parameter: New column name | 'myParsedDates' |
Results:
MyDateStrings | myParsedDates |
|---|---|
2/1/00 14:20 | 2000-02-01 14:20:00 |
4/5/10 11:25 | 2010-04-05 11:25:00 |
6/7/99 22:00 | 1999-06-07 22:00:00 |
13/7/1999 22:00 | 1999-07-13 22:00:00 |
12-20-1894 15:45:00 | 1894-12-20 15:45:00 |
08-12-1956 22:01:04 | 1956-08-12 22:01:04 |
Example - type parsing functions
This example shows how to use parsing functions for evaluating input values against the function-specific data type.
Functions:
Item | Description |
|---|---|
PARSEBOOL Function | Evaluates a String input against the Boolean datatype. If the input matches, the function outputs a Boolean value. Input can be a literal, a column of values, or a function returning String values. |
PARSEDATE Function | Evaluates an input against the default input formats or (if specified) an array of Datetime format strings in their listed order. If the input matches one of the formats, the function outputs a Datetime value. |
PARSEFLOAT Function | Evaluates a String input against the Decimal datatype. If the input matches, the function outputs a Decimal value. Input can be a literal, a column of values, or a function returning String values. |
PARSEINT Function | Evaluates a String input against the Integer datatype. If the input matches, the function outputs an Integer value. Input can be a literal, a column of values, or a function returning String values. |
Source:
The following table contains data on a series of races.
raceId | disqualified | date | racerId | time_sc |
|---|---|---|---|---|
1 | FALSE | 2/1/20 | 1 | 24.22 |
2 | f | 2/8/20 | 1 | 25 |
3 | no | 2/8/20 | 1 | 24.11 |
4 | n | 1-Feb-20 | 2 | 26.1 |
5 | TRUE | 8-Feb-20 | 2.2 | -25.22 |
6 | t | 2/8/2020 10:16:00 AM | 2 | 25.44 |
7 | yes | 2/1/20 | 3 | 24 |
8 | y | 2/8/20 | 33 | 29.22 |
9 | 0 | 2/8/20 | 3 | 24.78 |
10 | 1 | 1-Feb-20 | 4 | 26.2.1 |
11 | FALSE | 8-Feb-20 | 28.22 sec | |
12 | FALSE | 2/8/2020 10:16:00 AM | 4 | 27.11 |
As you can see, this dataset has variation in values (FALSE, f, no, n) and problems with the data.
Transformation:
When the data is first imported, it may be properly typed for each column. To use the parsing functions, these columns should be converted to String data type:
Transformation Name | |
|---|---|
Parameter: Columns | disqualified,date,racerId,time_sc |
Parameter: New type | String |
Now, you can parse individual columns.
disqualified column:
Transformation Name | |
|---|---|
Parameter: Columns | disqualified |
Parameter: Formula | PARSEBOOL($col) |
racerId column:
Transformation Name | |
|---|---|
Parameter: Columns | racerId |
Parameter: Formula | PARSEINT($col) |
time_sc column:
Transformation Name | |
|---|---|
Parameter: Columns | time_sc |
Parameter: Formula | PARSEFLOAT($col) |
date column:
For the date column, the PARSEDATE function supports a default set of Datetime formats. Since some of the listed formats are different from these defaults, you must specify all of the formats. These formats are specified as an array of string values as the second argument of the function:
Suggerimento
For the PARSEDATE function, it's useful to use the Preview to verify that all of the dates in the column are represented in the array of output formats. You can see the available output formats through the data type menu at the top of a column in the Transformer Page.
Transformation Name | |
|---|---|
Parameter: Columns | date |
Parameter: Formula | PARSEDATE($col, ['yyyy-MM-dd','yyyy\/MM\/dd','M\/d\/yyy hh:mm','MMMM d, yyyy','MMM d, yyyy']) |
After all of the date values have been standardized to the output format of the PARSEDATE function, you may choose to remove the time element of the values:
Transformation Name | |
|---|---|
Parameter: Column | date |
Parameter: Find | ` {digit}{2}:{digit}{2}:{digit}{2}{end}` |
Parameter: Replace with | '' |
Results:
After executing the above steps, the data appears as follows. Notes on each column's output are below the table.
raceId | disqualified | date | racerId | time_sc |
|---|---|---|---|---|
1 | false | 2020-02-01 | 1 | 24.22 |
2 | false | 2020-02-08 | 1 | 25 |
3 | false | 2020-02-08 | 1 | 24.11 |
4 | false | 2020-02-01 | 2 | 26.1 |
5 | true | 2020-02-08 | null | -25.22 |
6 | true | 2020-02-08 | 2 | 25.44 |
7 | true | 2020-02-01 | 3 | 24 |
8 | true | 2020-02-08 | 33 | 29.22 |
9 | false | 2020-02-08 | 3 | 24.78 |
10 | true | 2020-02-01 | 4 | null |
11 | false | 2020-02-08 | null | null |
12 | false | 2020-02-08 | 4 | 27.11 |
disqualified column:
The PARSEBOOL function normalizes all valid Boolean values to either
falseortrue.
racerId column:
The PARSEINT function writes invalid values as null values.
The function writes empty values as null values.
The value
33remains, since it is a valid Integer. This value should be fixed manually.
time_sc:
The PARSEFLOAT function writes the source value
25.00as25in output.The source value
-25.22remains. However, since this is time-based data, it needs to be fixed.Invalid values are written as nulls.
date column:
All values are written in the standardized format:
yyyy-MM-dd HH:mm:ss. Time data has been stripped.