Null attributes of result columns

Result columns allow null values if they are derived from:

• Any aggregate function but COUNT and COUNT_BIG
• Any column that allows null values
• A scalar function or expression with an operand that allows null values
• A host variable that has an indicator variable, an SQL parameter or variable, or in the case of Java™, a variable or expression whose type is able to represent a Java null value
• A result of a UNION or INTERSECT if at least one of the corresponding items in the select list is nullable
• An arithmetic expression in the outer select list
• A scalar-fullselect
• A user-defined scalar or table function
• A GROUPING SETS grouping-expression