3.5.7. CITYDB_OBJCLASS

The CITYDB_OBJCLASS package only provides two convenience functions to cast between table names and ID values of the OBJECTCLASS table. In contrast to the previously introduced packages these functions cannot be applied against different database schemas as this would require dynamic SQL. While it would not be problem when converting single values, the performance with dynamic SQL could be a lot worse when these functions are integrated in a full table scan. Therefore, for PostgreSQL they are now part of the ‘citydb’ schema as pure SQL functions. In Oracle, they make up another PL/SQL package.

Table 3.24 API of CITYDB_OBJCLASS package for Oracle
Function
Return Type
Explanation
objectclass_id_to_table_name
(objectclass_id)
VARCHAR2
Returns the corresponding table name to a given
object class ID
table_name_to_objectclass_ids
(table_name)
ID_ARRAY
Returns an array of object class IDs that a are
managed in the given table