ODBC

ODBC, or Open Database Connectivity, is a standard application programming interface (API) that enables programs to access data in database management systems (DBMS) using a uniform set of calls. By providing a common interface, ODBC allows software to obtain data from diverse databases without requiring database-specific code.

ODBC originated in the early 1990s as a joint effort between Microsoft and Simba Technologies to create a cross-database data access standard. Over time it has been maintained and extended by industry groups and vendors, and it has become available on multiple platforms, including Windows and various Unix-like systems through projects such as unixODBC and iODBC.

The typical ODBC architecture consists of four layers: the application, the ODBC Driver Manager, the database-specific ODBC driver, and the target DBMS. The Driver Manager loads the appropriate driver at runtime and provides the necessary environment for ODBC calls. Applications interact with the Driver Manager through the ODBC API, and the driver translates these calls into the database’s native protocol. Data sources can be defined as DSNs (Data Source Names) that store connection attributes, or connections can be established directly using a DSN-less connection string.

Database drivers are responsible for implementing the ODBC API against a particular DBMS, translating SQL statements and results to and from the DBMS’s native syntax. This enables applications to perform common operations such as connecting, preparing statements, executing queries, and retrieving results in a DBMS-agnostic way.

ODBC offers portability and reuse of existing data access code but depends on the quality of individual drivers. Limitations can include driver inconsistencies, feature gaps, and security considerations related to credential storage in DSNs.