ksql to convert a string to an array, then explode

Question

I'm working a topic that

+-----------------------------+------------------------------------------------------------+
|_ID                          |FULLDOCUMENT                                                |
+-----------------------------+------------------------------------------------------------+
|{"_data": "8262ECB4B900008"} |{"_id": {"$oid": "61cb1968838939009c7c9399"}, "categories": |
|                             |[{"$oid": "5c9afc56e4d34677a31b2087"}, {"$oid": "5c9b0bff9b6|
|                             |5d57b5297197f"}]                                            |

The FULLDOCUMENT is described as a string

FULLDOCUMENT      | VARCHAR(STRING)

but it's actually JSON object.

Within it, I have categories as an array

"categories": [{"$oid": "5c9afc56e4d34677a31b2087"}, {"$oid": "5c9b0bff9b65d57b5297197f"}]

And I would like to use EXPLODE function to explode it to something like below

+-----------------------------+
|CATEGORIES                   |
+-----------------------------+
| 5c9afc56e4d34677a31b2087    |
| 5c9b0bff9b65d57b5297197f    |
|                             |

I have tried to use different functions from ksqldb documentation but haven't managed to convert this to array, then explode it. Thank you for any suggestions!

Answer 1

We already implemented the required function (JSON_ITEMS) which will be available in our next release in a few weeks.