Skip to main content

HOST Function

Finds the host value from a valid URL. Input values must be of URL or String type and can be literals or column references.

In this implementation, a host value includes everything from the end of the protocol identifier (if present) to the end of the extension (e.g. .com).

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

URL literal examples:

host(&apos;<span class="nolink">http://www.example.com</span>&apos;)

Output: Returns the value www.example.com.

Column reference example:

host(myURLs)

Output: Returns the host values extracted from the myURLs column.

Syntax and Arguments

host(column_url)

Argument

Required?

Data Type

Description

column_url

Y

string

Name of column or String or URL literal containing the host value to extract

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

column_url

Name of the column or URL or String literal whose values are used to extract the host value.

  • Missing input values generate missing results.

  • Multiple columns and wildcards are not supported.

Usage Notes:

Required?

Data Type

Example Value

Yes

String literal or column reference (URL)

http://www.example.com

Examples

ヒント

For additional examples, see Common Tasks.

Example - Domain, Host, Subdomain, and Suffix functions

This examples illustrates how you can extract component parts of a URL using specialized functions for the URL data type.

Functions:

Item

Description

DOMAIN Function

Finds the value for the domain from a valid URL. Input values must be of URL or String type.

SUBDOMAIN Function

Finds the value a subdomain value from a valid URL. Input values must be of URL or String type.

HOST Function

Finds the host value from a valid URL. Input values must be of URL or String type and can be literals or column references.

SUFFIX Function

Finds the suffix value after the domain from a valid URL. Input values must be of URL or String type.

URLPARAMS Function

Extracts the query parameters of a URL into an Object. The Object keys are the parameter's names, and its values are the parameter's values. Input values must be of URL or String type.

FILTEROBJECT Function

Filters the keys and values from an Object data type column based on a specified key value.

Source:

Your dataset includes the following values for URLs:

URL

www.example.com

example.com/support

http://www.example.com/products/

http://1.2.3.4

https://www.example.com/free-download

https://www.example.com/about-us/careers

www.app.example.com

www.some.app.example.com

some.app.example.com

some.example.com

example.com

http://www.example.com?q1=broken%20record

http://www.example.com?query=khakis&app=pants

http://www.example.com?q1=broken%20record&q2=broken%20tape&q3=broken%20wrist

Transformation:

When the above data is imported into the application, the column is recognized as a URL. All values are registered as valid, even the numeric address.

To extract the domain and subdomain values:

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

DOMAIN(URL)

Parameter: New column name

'domain_URL'

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

SUBDOMAIN(URL)

Parameter: New column name

'subdomain_URL'

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

HOST(URL)

Parameter: New column name

'host_URL'

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

SUFFIX(URL)

Parameter: New column name

'suffix_URL'

You can use the Wrangle in the following transformation to extract protocol identifiers, if present, into a new column:

Transformation Name

Extract text or pattern

Parameter: Column to extract from

URL

Parameter: Option

Custom text or pattern

Parameter: Text to extract

`{start}%*://`

To clean this up, you might want to rename the column to protocol_URL.

To extract the path values, you can use the following regular expression:

注記

Regular expressions are considered a developer-level method for pattern matching. Please use them with caution. See Text Matching.

Transformation Name

Extract text or pattern

Parameter: Column to extract from

URL

Parameter: Option

Custom text or pattern

Parameter: Text to extract

/[^*:\/\/]\/.*$/

The above transformation grabs a little too much of the URL. If you rename the column to path_URL, you can use the following regular expression to clean it up:

Transformation Name

Extract text or pattern

Parameter: Column to extract from

URL

Parameter: Option

Custom text or pattern

Parameter: Text to extract

/[!^\/].*$/

Delete the path_URL column and rename the path_URL1 column to the deleted one. Then:

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

URLPARAMS(URL)

Parameter: New column name

'urlParams'

If you wanted to just see the values for the q1 parameter, you could add the following:

Transformation Name

New formula

Parameter: Formula type

Single row formula

Parameter: Formula

FILTEROBJECT(urlParams,'q1')

Parameter: New column name

'urlParam_q1'

Results:

For display purposes, the results table has been broken down into separate sets of columns.

Column set 1:

URL

host_URL

path_URL

www.example.com

www.example.com

example.com/support

example.com

/support

http://www.example.com/products/

www.example.com

/products/

http://1.2.3.4

1.2.3.4

https://www.example.com/free-download

www.example.com

/free-download

https://www.example.com/about-us/careers

www.example.com

/about-us/careers

www.app.example.com

www.app.example.com

www.some.app.example.com

www.some.app.example.com

some.app.example.com

some.app.example.com

some.example.com

some.example.com

example.com

example.com

http://www.example.com?q1=broken%20record

www.example.com

http://www.example.com?query=khakis&app=pants

www.example.com

http://www.example.com?q1=broken%20record&q2=broken%20tape&q3=broken%20wrist

www.example.com

Column set 2:

URL

protocol_URL

subdomain_URL

domain_URL

suffix_URL

www.example.com

www

example

com

example.com/support

example

com

http://www.example.com/products/

http://

www

example

com

http://1.2.3.4

http://

https://www.example.com/free-download

https://

www

example

com

https://www.example.com/about-us/careers

https://

www

example

com

www.app.example.com

www.app

example

com

www.some.app.example.com

www.some.app

example

com

some.app.example.com

some.app

example

com

some.example.com

some

example

com

example.com

example

com

http://www.example.com?q1=broken%20record

http://

www

example

com

http://www.example.com?query=khakis&app=pants

http://

www

example

com

http://www.example.com?q1=broken%20record&q2=broken%20tape&q3=broken%20wrist

http://

www

example

com

Column set 3:

URL

urlParams

urlParam_q1

www.example.com

example.com/support

http://www.example.com/products/

http://1.2.3.4

https://www.example.com/free-download

https://www.example.com/about-us/careers

www.app.example.com

www.some.app.example.com

some.app.example.com

some.example.com

example.com

http://www.example.com?q1=broken%20record

{"q1":"broken record"}

{"q1":"broken record"}

http://www.example.com?query=khakis&app=pants

{"query":"khakis","app":"pants"}

http://www.example.com?q1=broken%20record&q2=broken%20tape&q3=broken%20wrist

{"q1":"broken record", "q2":"broken tape",

"q3":"broken wrist"}

{"q1":"broken record"}