solidDB^® supports external stored procedures written in C programming language. External stored procedures enable you to expand the server functionality by writing a C program.

The external stored procedures are registered with the CREATE PROCEDURE (external) statement.

The external procedures are accessed using the standard dynamic library interface as provided by the operating system (shared libraries in Linux and UNIX, DLLs in Windows). To enable use of external stored procedures, you must link your application dynamically to solidDB^® using shared memory access (SMA) or linked library access (LLA).

The external procedures are called with the same CALL statement syntax as SQL stored procedures; the control of the thread is passed to the external library routine until it returns. Furthermore, the database interface of the external procedures is similar to that of an ODBC application, except that the connection handle (hdbc) is passed to the external routine, and it can immediately start using it without establishing the connection.

The external procedures are removed with the DROP PROCEDURE statement.