( [resource link_identifier] )
fbsql_insert_id() returns the ID generated for
an column defined as DEFAULT UNIQUE by the previous INSERT query
using the given link_identifier. If
link_identifier isn't specified, the last
opened link is assumed.
fbsql_insert_id() returns 0 if the previous
query does not generate an DEFAULT UNIQUE value. If you need to
save the value for later, be sure to call fbsql_insert_id()
immediately after the query that generates the value.
The value of the FrontBase SQL function
fbsql_insert_id() always contains the most
recently generated DEFAULT UNIQUE value, and is not reset