Incorrect JSON field content syntax resulting in ALL entries/tags being added instead of none.

[KBjana]

Description / Steps

I was doing a JSON export from an old CMS, which had, when the field was empty was outputting either a single space character ( ) or a (,) character.

An entry field was mapped to data that featured a (,) character when there was supposed to be no data instead of id numbers. eg. "craft_product_cat_ids": ","

A Tag field was mapped to data that featured a ( ) character when there was supposed to be no tags. eg. "hosted_escorted": " "

For both of these fields instead of being empty, they were given all the entries / tags.

Additional info

• Craft version: 5.5.2
• PHP version: 8.2.24
• Database driver & version: MySQL 8.0.40
• Plugins & versions: 6.5.0