sql - Associate one column in table with two existing tables -



sql - Associate one column in table with two existing tables -

my db has next tables:

resource: resources can uploaded on site groups: groups on site users: users on site (not part of grouping if like)

now, when 1 uploads resource currently, ownership of resource given it's uploader default. resource table has column ownerid foreign key association user table.

but now, has changed such ownership of resource given either user or entire group.

i'm trying decide migration scheme, move owner beingness user entity either user or group. intuition when uploads material, can take owner user or entire group.

currently migration plans involves:

add ownertype (user, group, global) , userowner , groupowner within material table (probably worse normalized table). ownertype global if owner --or-- group if owner group entity else user. then when i'm querying resource table, can check ownertype condionally select owner either user table or group table.

i not know if way. i'm using entity framework, , things started ugly user , group hardly have relationaship require me create generalized entity.

can expert guide me on this? considered migration plan in case? help or suggestions.

sql linq orm migration database-migration

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