LIMIT is a method that returns the maximum number of elements permitted in a collection.
LIMIT applies only to varrays. The syntax for using
collection is the name of a collection.
For an initialized varray,
LIMIT returns the maximum size limit determined by the varray type definition. If the varray is uninitialized (that is, it's a null varray), an exception is thrown.
For an associative array or an initialized nested table,
NULL. If the nested table is uninitialized (that is, it's a null nested table), an exception is thrown.