RIGHTFIND Function

Returns the index value in the input string where the last instance of a matching string is located. Search is conducted right-to-left.

Input can be specified as a column reference or a string literal, although string literal usage is rare.

  • A column reference can refer to a column of String, Object, or Array type, which makes the RIGHTFIND function useful for filtering data before it has been completely un-nested into tabular data.
  • Starting location is specified from the end of the string.
  • Returned value is from the beginning of the string, regardless of the string index value.
  • If no match is found, the function returns a null value.
  • If you need to determine if a value is in an array or not, you can use the MATCHES function, which returns a true/false response. See MATCHES Function.

You can also search a string from the left. For more information, see FIND Function.

Basic Usage

Column reference example:

derive type:single value: RIGHTFIND(MyName,'find this',true,0)

Output: Searches the MyName column value for the last instance of the string find this from the end of the value, ignoring case. If a match is found, the index value from the beginning of the string is written to the new column.

String literal example:

derive type:single value: RIGHTFIND('Hello, World','lo',false,2)

Output: Searches the string Hello, World for the string lo, in a case-sensitive search from the third-to-last character of the string. Since the match is found at the fourth character from the left, the value 3 is written to the new column.

If example:

derive type:single value: IF(RIGHTFIND(SearchPool,'FindIt') >= 0, 'found it', '') as: 'Finds'

Output: Searches the SearchPool column value for the string FindIt from the end of the value (default). Default behavior is to not ignore case. If the string is found, the new column Finds contains the value found it. Otherwise, the column is empty.

Syntax

derive type:single value:RIGHTFIND(column_string,string_pattern,[ignore_case], [start_index])

ArgumentRequired?Data TypeDescription
column_stringYstringName of the column or string literal to be applied to the function
string_patternYstringString literal or pattern to find
ignore_caseNbooleanIf true, a case-insensitive match is performed. Default is false.
start_indexNinteger (non-negative)

If specified, this value identifies the start index value of the source data to search for a match.

NOTE: This value is specified from the end of the string.

If not specified, the entire string is searched.

For more information on syntax standards, see Language Documentation Syntax Notes.

column_string

Name of the item to be searched. Valid values can be:

  • String literals must be quoted ('Hello, World').
  • column reference to any type that can be inferred as a string, which encompasses all values.

Missing values generate the start-index parameter value.

  • Multiple values and wildcards are not supported.

Usage Notes:

Required?Data TypeExample Value
YesString literal or column reference (String, Array, or Object)myColumn

string_pattern

String literal or pattern to find. This value can be a string literal, a Cloud Dataprep pattern, or a regular expression.

  • Missing string or column values generate the start-index parameter value.
    • String literals must be quoted ('Hello, World').
  • Multiple values and wildcards are not supported.

Usage Notes:

Required?Data TypeExample Value
YesString literal or pattern'Hello'

ignore_case

If true, the RIGHTFIND function ignores case when trying to match the string literal or pattern value.

Default value is false, which means that case-sensitive matching is performed by default.

Usage Notes:

Required?Data TypeExample Value
NoBooleantrue

start_index

The index of the character in the column or string literal value at which to begin the search, from the end of the string. For example, a value of 2 instructs the RIGHTFIND function to begin searching from the third character in the column or string value.

NOTE: Index values begin at 0. If not specified, the default value is 0, which searches the entire string from the end of the string.

  • Value must be a non-negative integer value.

  • If this value is greater than the length of the string, then no match is possible.

Usage Notes:

Required?Data TypeExample Value
NoInteger (non-negative)2

Examples

Example - Locate filenames in a URL

In this example, you must extract filenames from a column of URL values. Some rows do not have filenames, and there is some variation in the structure of the URLs.

Source:

URL
www.example.com
http://www.example.com
http://www.example.com/test_app
http://www.example.com/index.html
http://www.example.com/resources/mypic.jpg
http://www.example.com/pages/mypage.html
http://www.example.com/resources/styles.css
www.example.com/resources/styles.css

Transform:

To preserve the original column, you can use the following to create a working version of the source:

derive type:single value:URL as:'filename'

You can use the following to standardize the formatting of the working column:

replace: col:filename on:'http:' with:'' ignoreCase:true

Tip: You may need to modify the above to use a Cloud Dataprep pattern to also remove https://.

The next two steps calcuate where in the filename values the forward slash and dot values are located, if at all. The following calculates the

derive type:single value: RIGHTFIND(filename,"\/",true,0) as: 'rightFindSlash'

derive type:single value: RIGHTFIND(filename,".",true,0) as: 'rightFindDot'

If either of the above values is 0, then there is no filename present:

set col:filename value:IF((rightFindSlash == 0) || (rightFindDot == 0), '', RIGHT(filename,(LEN(filename)-rightFindSlash)))

Results:

After removing the intermediate columns, you should end up with something like the following:

URLfilename
www.example.com
http://www.example.com
http://www.example.com/test_app
http://www.example.com/index.htmlindex.html
http://www.example.com/resources/mypic.jpgmypic.jpg
http://www.example.com/pages/mypage.htmlmypage.html
http://www.example.com/resources/styles.cssstyles.css
www.example.com/resources/styles.cssstyles.css

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