Encodes all characters that are not unreserved using percent-encoding. Unreserved characters are defined according to W3C RFC 3986. 
unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"

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Syntax

URL_ENCODE(<expression>)

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Parameters

ParameterDescriptionSupported input types
<expression>The string to be encoded.TEXT

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Return Type

TEXT

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Example

The example below converts characters that are not unreserved that appear in the parameter section of the URL: 
SELECT CONCAT('https://www.firebolt.io/?', URL_ENCODE('example_id=1&hl=en'));
Returns: https://www.firebolt.io/?example_id%3D1%26hl%3Den