Oracle PL/SQL Programming: A Developer's Workbook

Intermediate

Q:
28-26.	The PL/SQL gateway uses the named notation to translate a procedure call made from the Web into a corresponding procedure call inside the RDBMS. Named notation attempts to map the names and datatypes onto a corresponding procedure. Any error, such as misspelling a parameter name or a mismatched type, results in an unhandled exception. There are three important implications for web-application development: The name given to a parameter in a query string or on an HTML form must exactly match the name of a corresponding formal parameter. Developing and using a best-practices naming convention can help reduce this error. The datatype assigned to a parameter must match the datatype assigned to the corresponding formal parameter. Declaring all parameters as VARCHAR2 helps reduce this error. You must supply a value for all parameters that do not have a default value. Declaring default values helps reduce this error.
Q:
28-27.	You can call a procedure using just its name when you have a base URL to supply the missing server, port, and virtual schema mapping. This is called relative URL.
Q:
28-28.	The procedure call results in an unhandled exception; it does not print “Invalid Number”, even though this is clearly the intended purpose of the exception section. The flaw in the design is that, while the I_val parameter has been declared as a NUMBER, the actual value passed is a text string. When the PL/SQL gateway attempts to match the call to an existing procedure, it compares ...