Contents:
Contents:
- If a string begins or ends with spaces, tabs, or other non-visible characters, they are removed by this function.
- The
TRIMfunction does not remove whitespace between non-whitespace values, such as spaces between words. To remove that type of whitespace, useREMOVEWHITESPACE. See REMOVEWHITESPACE Function. - The
TRIMfunction can be used with theTRIMQUOTESfunction, which removes leading and trailing single- and double-quotes. For more information, see TRIMQUOTES 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
Column reference example:
trim(MyName)
Output: Returns the values of the MyName column value with whitespace removed from the beginning and the end.
String literal example:
trim(' Hello, World ')
Output: Returns the string:Hello, World.
Syntax and Arguments
trim(column_string)
| Argument | Required? | Data Type | Description |
|---|---|---|---|
| column_string | Y | string | Name of the column or string literal to be applied to the function |
For more information on syntax standards, see Language Documentation Syntax Notes.
column_string
Name of the column or string constant to be trimmed.
- Missing string or column values generate missing string results.
- String constants must be quoted (
'Hello, World'). - Multiple columns and wildcards are not supported.
Usage Notes:
| Required? | Data Type | Example Value |
|---|---|---|
| Yes | String literal or column reference | myColumn |
Tip: For additional examples, see Common Tasks.
Examples
Example - Trimming leading and trailing whitespace
In this example, whitespace values are identified according to this table. The ASCII value column identifies that ASCII character value that represents the character.
- The ASCII character set is a standard method for representing keyboard and special characters on the computer. For more information on ASCII, see http://www.asciitable.com/.
| Value | Definition | ASCII value |
|---|---|---|
| (space) | spacebar | Char(32) |
| (tab) | tab character | Char(9) |
| (cr) | carriage return | Char(13) |
| (nl) | newline | Char(10) |
Source:
In the following example dataset, input values are represented in the mystring. The values in the table above are represented in the string values below.
| mystring |
|---|
| Here's my string. |
| (space)(space)Here's my string.(space)(space) |
| (tab)Here's my string.(tab) |
| (cr)Here's my string.(cr) |
| (nl)Here's my string.(nl) |
| (space)(space)(tab)Here's my string.(tab)(space)(space) |
| (space)(space)(tab)(cr)Here's my string.(cr)(tab)(space)(space) |
| (space)(space)(tab)(nl)(cr)Here's my string.(cr)(nl)(tab)(space)(space) |
Input:
When the above CSV data is imported into the Transformer page, it is represented as the following:
| mystring |
|---|
| Here's my string. |
| (space)(space)Here's my string.(space)(space) |
| "(tab)Here's my string.(tab)" |
| "(cr)Here's my string.(cr)" |
| "(nl)Here's my string.(nl)" |
| "(space)(space)(tab)Here's my string.(tab)(space)(space)" |
| "(space)(space)(tab)(cr)Here's my string.(cr)(tab)(space)(space)" |
| "(space)(space)(tab)(nl)(cr)Here's my string.(cr)(nl)(tab)(space)(space)" |
Transformation:
You might notice the quote marks around most of the imported values.
NOTE: If an imported string value contains tab, carriage return, or newline values, it is bracketed by double quotes.
The first step is to remove the quote marks. You can select one of the quote marks in the data grid and then select the appropriate Replace suggestion card. The transform should look like the following:
| Transformation Name | Replace text or pattern |
|---|---|
| Parameter: Column | mystring |
| Parameter: Find | `"` |
| Parameter: Replace with | '' |
| Parameter: Match all occurrences | true |
Now, you can apply the trim function:
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | trim(mystring) |
| Parameter: New column name | 'trim_mystring' |
Results:
In the generated trim_mystring column, you can see the cleaned strings:
| mystring | trim_mystring |
|---|---|
| Here's my string. | Here's my string. |
| (space)(space)Here's my string.(space)(space) | Here's my string. |
| "(tab)Here's my string.(tab)" | Here's my string. |
| "(cr)Here's my string.(cr)" | Here's my string. |
| "(nl)Here's my string.(nl)" | Here's my string. |
| "(space)(space)(tab)Here's my string.(tab)(space)(space)" | Here's my string. |
| "(space)(space)(tab)(cr)Here's my string.(cr)(tab)(space)(space)" | Here's my string. |
| "(space)(space)(tab)(nl)(cr)Here's my string.(cr)(nl)(tab)(space)(space)" | Here's my string. |
Tip: If any bracketing double quotes are removed, then tab, carriage return, and newline values are trimmed by the TRIM function.
Example - String cleanup functions together
Functions:
| Item | Description |
|---|---|
| TRIM Function | Removes leading and trailing whitespace from a string. Spacing between words is not removed. |
| REMOVEWHITESPACE Function | Removes all whitespace from a string, including leading and trailing whitespace and all whitespace within the string. |
| REMOVESYMBOLS Function | Removes all characters from a string that are not letters, numbers, accented Latin characters, or whitespace. |
Source:
In the following (space) and (tab) indicate space keys and tabs, respectively. Carriage return and newline characters are also supported by whitespace functions.
| Strings | source |
|---|---|
| String01 | this source(space)(space) |
| String02 | (tab)(tab)this source |
| String03 | (tab)(tab)this source(space)(space) |
| String04 | this source's? |
| String05 | Why, you @#$%^&*()! |
| String06 | this söurce |
| String07 | (space)this söurce |
| String08 | à mañana |
Transformation:
The following transformation steps generate new columns using each of the string cleanup functions:
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | TRIM(source) |
| Parameter: New column name | 'trim_source' |
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | REMOVEWHITESPACE(source) |
| Parameter: New column name | 'removewhitespace_source' |
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | REMOVESYMBOLS(source) |
| Parameter: New column name | 'removesymbols_source' |
Results:
| Strings | source | removesymbols_source | removewhitespace_source | trim_source |
|---|---|---|---|---|
| String01 | this source(space)(space) | this source(space)(space) | thissource | this source |
| String02 | (tab)(tab)this source | (tab)(tab)this source | thissource | this source |
| String03 | (tab)(tab)this source(space)(space) | (tab)(tab)this source(space)(space) | thissource | this source |
| String04 | this source's? | this sources | thissource's? | this source's? |
| String05 | "Why, you @#$%^&*()!" | Why you | Why,you@#$%^&*()! | Why, you @#$%^&*()! |
| String06 | this söurce | this söurce | thissöurce | this söurce |
| String07 | (space)this söurce | (space)this söurce | thissöurce | this söurce |
| String08 | à mañana | à mañana | àmañana | à mañana |
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