sql - How to find out if row being referenced changed? -

i've been thinking , looking solution problem don't know how search it. sorry if it's been answered.

context

i have app has persistence, , data provided rest api. 1 off calls supposed return new stuff, , comparing last time data retrieved time data changed. if changes newer retrieve, if not don't.

suppose we're working on schema:

company( id, address_id references address( id ), updated_at, ... )  equipment( id, address_id references address( id ), updated_at, ... )  address( id, updated_at, ... ) 

there trigger updates updated_at column on insert or update.

the api response when company , it's referenced address updated , equipment updated:

{ company:{ info, address:{ info } },   equipment:{ info } } 

the problem

i'm retrieving company or equipment when changes occurred, , i'm retrieving address if company , equipment changed , address changed well. the problem when address changed, because api never return changes. can't return addresses changed because imply in lot of unnecessary data being downloaded.

i create query like:

select a.* company c, equipment e, address  a.id = c.address_id or     a.id = e.address_id ,    a.updated_at > "2000-01-01 00:00:00" 

but doing response format lost, or necessary lot of server work relating each x returned it's respective element.

the solution thought creating trigger updates company's or equipment's updated_at column when address updated. however, doing retrieve old information tables references address, it's ok doing know if there better solution.