Oracle in a Nutshell

Keywords

proc_name

Name of the wrapper procedure.

LANGUAGE C

Language in which the external routine was written (default is C).

library_name

Name of the library created with the CREATE LIBRARY statement.

external_name

Name of the external routine as it appears in the library. This name defaults to the wrapper package name. PL/SQL package names are usually saved in uppercase, so the external_name may need to be enclosed in double quotes to preserve case.

AGENT IN ( agent_name )

Specifies the value of the agent as a formal PL/SQL parameter to the call spec.

WITH CONTEXT

Used to pass a context pointer to the external routine, so it can make Oracle Call Interface (OCI) calls back to the database.

PARAMETERS

Identify the external_parameter_list, which is a comma-delimited list containing the position and datatype of parameters that get passed to the external routine. The purpose of this clause is to resolve inconsistencies between the way PL/SQL and C handle variables. The syntax for each parameter in the list is:

{CONTEXT | RETURN | parameter_name [property]} 
   [BY REFERENCE] [external_datatype]

where:

CONTEXT

Indicates the position in the parameter list at which the context pointer will be passed. It is required if the WITH CONTEXT clause is being used to pass a context pointer to the called program. By convention, CONTEXT appears as the first parameter in the external parameter list. If CONTEXT is used, the property, BY REFERENCE, and external_datatype optional sections are invalid.

RETURN ...