The facility represents a building or group of small buildings. There may be many buildings in a single portfolio and each building in ManagingEnergy can have a lot of information attached to it. Information such as HVAC equipment, energy reduction opportunities, utility meters, photos, schematics, etc. Facilities are stored, surprisingly enough, in a table named tblFacility and are uniquely identified by a field named FacilityCode. This table is the parent to many tables in ManagingEnergy as seen below.
Here is a listing of all the HVAC equipment tables:
The above tables are all linked via ProjectID and FacilityCode. The tables below are all the non-HVAC equipment tables and are also linked by ProjectID and FacilityCode.
There are also tables in which the relationship is managed via triggers. This is usually due to the fact that only one foreign key constraint can force an update or delete when it is altered. If a table has more than one foreign key then triggers are used to maintain the relationship.