Handling special characters in JSON keys during transformation

When transforming JSON documents into a tabular format, you might stumble upon certain keys that produce an error message.

This document is valid JSON, but generates an error, such as "XPath syntax error at char 0 in {80x}:
Separator needed after numeric literal" when parsing it in Data Virtuality.

{
  "80x60": "https://datavirtuality.com/wp-content/uploads/sites/2/2016/09/solutions@3x.png",
}

SELECT xmlTable.*
FROM (call "file".getFiles('key_example.json')) f,
XMLTABLE(XMLNAMESPACES( 'http://www.w3.org/2001/XMLSchema-instance' as "xsi" ),'/root' PASSING JSONTOXML('root',to_chars(f.file,'UTF-8'))
 COLUMNS "80x60" STRING PATH '80x60'
) "xmlTable"

This is due to the fact that Data Virtuality internally transforms the JSON document into an XML document for easier parsing. Since an identifier in XML may not start with a number, it gets escaped and rewritten to _u0038_0x60. Hence, you will need to pass this value as an XPath expression for referring to your JSON key.

SELECT xmlTable.*
FROM (call "file".getFiles('key_example.json')) f,
XMLTABLE(XMLNAMESPACES( 'http://www.w3.org/2001/XMLSchema-instance' as "xsi" ),'/root' PASSING JSONTOXML('root',to_chars(f.file,'UTF-8'))
 COLUMNS "80x60" STRING PATH '_u0038_0x60'
) "xmlTable"

In order to look up this transformed key name, you can run the XMLESCAPENAME function (SELECT XMLESCAPENAME('80x60', true)) which will return the correct name of the node in the XML document.

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