Unified sharing database review #64999

Observations and thoughts on the unified sharing db schema:

Overall

• refactor: map sharing instances to ints, and add instance to indices #65512 Probably makes sense to create a mapping for instances. It's not as bad as the class names where, but there is still there is 1 per share + 2 per recipient and they are often included in indices.

• refactor: map sharing instances to ints, and add instance to indices #65512 Instance length should be 255, not 128, as 255 is the maximum length of a domain name.

sharing_share

• refactor: store state enums in unified sharing as ints #65509 can state be an int instead of a string?
• refactor: map sharing instances to ints, and add instance to indices #65512 add index by owner

sharing_share_properties

• maybe switch to text or blob for propety_value

sharing_share_recipeints

• refactor: map sharing instances to ints, and add instance to indices #65512 recipient instance is missing from unique index

sharing_share_sources

• can we get away with an integer source_value, having a varchar(255) in the pkey isn't great
• add index by source_class_id+source_value, (same varchar concern)

sharing_share_user_status

• no instance for the user? Maybe reference sharing_share_recipient.id instead of user?
• refactor: store state enums in unified sharing as ints #65509 can status be an int?