Creates a schema.
a schema definition, along with a corresponding package definition. The owner of the schema
will be defined as the user who issues this command. A schema created
in this manner will not appear in INFORMATION_SCHEMA.SCHEMATA until
a table has been created within the schema.
If IF NOT EXISTS was specified and the schema already exists,
this command performs no action. If IF NOT EXISTS was not specified
but a schema with the same name already exists, SQLCODE -476 is returned.