images column is type jsonb.
Reading Postgres docs on the - operator for text it states:
Delete key/value pair or string element from left operand. Key/value pairs are matched based on their key value.
However, I am not having success. After I run my update I see the element in the array still exists. Is this because it is the only element in the array? If so, how would I deal with such a situation?
dev_dolphin_db=# update listings set images = images - 'filename' where listings.id = 2;
UPDATE 1
id | 2
created_at | 2017-04-20 04:19:41.009022+00
posted_by | 101090922
images | [{"review": "/9j/4AAQSC1LnS//2Q==", "filename": "3/2/image-3-2-1492661981049.jpeg"}]
If the hash is consistently in the 0th index of the jsonb array, you can delete it with
dev_dolphin_db=# update listings set images = images #- '{0,filename}' where listings.id = 2;
This uses the #- operator which postgres describes as:
Delete the field or element with specified path (for JSON arrays, negative integers count from the end)