A method of searching a biometric database includes storing biometric data corresponding to a number of users in a database, and defining one or more data subsets in the database according to inputs from users expecting to pass through a given biometric acquisition device that is linked with the database within a certain time period. A search initiated by the given acquisition device at a given time is then scaled down to only those data subsets defined by the inputs from those users expecting to pass through the acquisition device at the given time. This modification of the database and database search is performed continuously and automatically based on dynamic information provided by other automatic and/or manual systems, and then optionally the information on the databases can be automatically modified or deleted based either on a biometric match result or based on rules encoded in the database records.