Specify a routine name
You specify a name for the SPL routine immediately following
the CREATE PROCEDURE or CREATE FUNCTION statement and before the parameter
list, as the figure shows.
HCL OneDB™ allows
you to create more than one SPL routine with the same name but with
different parameters. This feature is known as routine overloading.
For example, you might create each of the following SPL routines in
your database:
CREATE PROCEDURE multiply (a INT, b FLOAT)
CREATE PROCEDURE multiply (a INT, b SMALLINT)
CREATE PROCEDURE multiply (a REAL, b REAL)
If you call a routine with the name multiply(), the database server evaluates the name of the routine and its arguments to determine which routine to execute.
Routine resolution is the
process in which the database server searches for a routine signature
that it can use, given the name of the routine and a list of arguments.
Every routine has a signature that uniquely identifies
the routine based on the following information:
- The type of routine (procedure or function)
- The routine name
- The number of parameters
- The data types of the parameters
- The order of the parameters
The routine signature is used in a CREATE, DROP, or EXECUTE
statement if you enter the full parameter list of the routine. For
example, each statement in the following figure uses a routine signature.