Concurrency Control

Two-Phase Locking (Deadlock Prevention)

dBASE employs a 2PL–style concurrency control scheme implemented through coarse-grained file and record locks rather than a full transactional lock manager. In multi-user deployments, dBASE relies on the underlying operating system's file-locking primitives to acquire locks before modifying database files or records, preventing concurrent writers from making conflicting updates. Once a lock is obtained, it is held for the duration of the update operation and released afterward.

Data Model

Relational

Isolation Levels

Not Supported

Query Execution

Tuple-at-a-Time Model

Query Interface

Custom API

System Architecture

Shared-Everything