Postgres jsonb_set concatenate current value

Question

I'm trying to use jsonb_set to update a range of json objects within my database. I can get a query working that updates the object with a string value, however I cannot seem to get it to update using the current value.

UPDATE entity
SET properties = jsonb_set(properties, '{c_number}', concat('0', properties->>'c_number'))
WHERE type = 1 and length(properties->>'c_number') = 7

The above doesn't work in its current format, I think the issue is the properties->>'c_number' inside the jsonb_set. Is there a way I can access the current value and simply add a leading 0?

Answer 1

Found a solution:

UPDATE entity
SET properties = jsonb_set(properties, '{c_number}', concat('"0', properties->>'c_number', '"')::jsonb)
WHERE type = 1 and length(properties->>'c_number') = 7