The key icons () represent primary keys.

The key icons that connect tables () represent the parent-child relationship between those tables.

The FKs are referred to as Sequential Identifiers (SID), which are unique identifiers generated by the application.

Table properties are dynamic, which means they display information only when the user selects certain configuration options.

In the AIRResult database, the primary keys point toward the Dim tables, which are the main (parent) tables that store data about the exposure objects (such as contract, location, layer, or accumulator). The (child) By tables, which store the analysis results, contain the foreign keys (FK) that reference the primary keys in the parent tables.

Check out the following relationship mappings to learn more about the relationship between the primary and foreign keys in AIR Databases.

Description	Mapping
One to zero or one: In the child table, the referencing column is unique, but not mandatory. In this case, the column from the parent table can refer to one or zero entries from the child table.
One to one or many: In the child table, the referencing column is mandatory, but not unique. In this case, the column from the parent table can refer to one (mandatory) or many.
One to one: In the child table, the referencing column is mandatory and unique. In this case, the column from the parent table can refer only to one entry from the child table.
One to zero or many: In the child table, the referencing column is not mandatory, nor unique. In this case, the parent table (1) can refer to zero or many entries in the child table (2).