mdB

MDB is an acronym that can refer to several distinct concepts depending on context. In computing, MDB most commonly stands for Memory-Mapped Database, a class of database design that stores its data in a memory-mapped file. This approach allows applications to access data via virtual memory, often resulting in fast reads and simplified transaction handling. The best-known implementation is LMDB (Lightning Memory-Mapped Database), which uses a memory-mapped, copy-on-write architecture and a database API with identifiers starting with MDB_.

Microsoft Access Database (.mdb) refers to the older Jet/ACE database format used by Microsoft Access prior to the .accdb era. MDB files store relational data in tables and support SQL queries, forms, reports, and other Access features. They are commonly found in Windows environments and legacy applications. Over time, many deployments migrated to the newer .accdb format, but .mdb files remain in use in some systems.

Multilateral Development Bank (MDB) is a term for a financial institution created by multiple countries to provide development financing and technical assistance to other countries. Examples include major regional and international banks such as the Asian Development Bank, African Development Bank, Inter-American Development Bank, and European Bank for Reconstruction and Development, as well as the World Bank Group’s development operations. MDBs typically offer loans, grants, guarantees, and advisory services to support infrastructure, education, health, and governance projects.

mdb (lowercase) also denotes the Modular Debugger, a Unix-like system debugger used on platforms such as Solaris and Illumos for post-mortem analysis and live debugging. It analyzes core dumps, inspects memory, and examines program state through a command-driven interface.

Context determines which MDB meaning applies.