A reference type with a target type of T can be assigned to a reference type column that is also a reference type with target type of S where S is a supertype of T. If an assignment is made to a scoped reference column or variable, no check is performed to ensure that the actual value being assigned exists in the target table or view defined by the scope.
Assignment to host variables is done based on the representation type of the reference type. That is, it follows the rule:
If the target of the assignment is a column, and the right hand side of the assignment is a host variable, the host variable must be explicitly cast to the reference type of the target column.
Numbers are compared algebraically; that is, with regard to sign. For example, -2 is less than +1.
If one number is an integer and the other is decimal, the comparison is made with a temporary copy of the integer, which has been converted to decimal.
When decimal numbers with different scales are compared, the comparison is made with a temporary copy of one of the numbers that has been extended with trailing zeros so that its fractional part has the same number of digits as the other number.
If one number is floating-point and the other is integer or decimal, the comparison is made with a temporary copy of the other number, which has been converted to double-precision floating-point.
Two floating-point numbers are equal only if the bit configurations of their normalized forms are identical.