Berkeley DB

Logically Renumbering Records

Records stored in the Queue and Recno access methods are accessed by logical record number. In all cases in Btree databases, and optionally in Recno databases (see the DB→set_flags function and the DB_RENUMBER flag for more information), record numbers are mutable. This means that the record numbers may change as records are added to and deleted from the database. The deletion of record number 4 causes any records numbered 5 and higher to be renumbered downward by 1; the addition of a new record after record number 4 causes any records numbered 5 and higher to be renumbered upward by 1. In all cases in Queue databases, and by default in Recno databases, record numbers are not mutable, and the addition or deletion ...