CAN_JSON_PARSE function - Amazon Redshift
SyntaxArgumentsReturn typeUsage notesExamples
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CAN_JSON_PARSE function

The CAN_JSON_PARSE function parses data in JSON format and returns true if the result can be converted to a SUPER value using the JSON_PARSE function.

Syntax

CAN_JSON_PARSE( {json_string | binary_value} )

Arguments

json_string

An expression that returns serialized JSON in VARCHAR form.

binary_value

A VARBYTE type binary value.

Return type

BOOLEAN

Usage notes

  • CAN_JSON_PARSE returns false for empty strings. It returns NULL when the input argument is null.

Examples

The following example shows CAN_JSON_PARSE running on a properly formed JSON array using a CASE condition. It returns true, so Amazon Redshift runs the JSON_PARSE function on the example value. 

SELECT CASE 
            WHEN CAN_JSON_PARSE('[10001,10002,"abc"]')
            THEN JSON_PARSE('[10001,10002,"abc"]')
        END;

 case
---------------------
'[10001,10002,"abc"]'

The following example shows CAN_JSON_PARSE running on a value that isn’t JSON format using a CASE condition. It returns false, so Amazon Redshift returns the segment in the ELSE clause of the CASE condition instead. 

SELECT CASE 
            WHEN CAN_JSON_PARSE('This is a string.')
            THEN JSON_PARSE('This is a string.')
            ELSE 'This is not JSON.'
        END;

 case
---------------------
"This is not JSON."