You cannot invoke a void static method using a simple SQL execute command. Rather, you must place the invocation of the void static method in a select statement.
For example, suppose that a Java class C has a void static method M(...), and assume that M( ) performs an action you want to invoke in SQL. For example, M( ) can use JDBC calls to perform a series of SQL statements that have no return values, such as create or drop, that would be appropriate for a void method.
You must invoke the void static method in a select command, such as:
select C.M(...)
To allow void static methods to be invoked using a select, void static methods are treated in SQL as returning a value of datatype int with a value of null.