Is null: isnull

Syntax

isnull ( op )

Input parameters

op	the operand

Examples of valid syntaxes

isnull(DS_1)

Semantics for scalar operations

The operator returns true if the value of the operand is null, false otherwise. For example:

isnull(“Hello”) gives **false**

isnull(**null**) gives **true**

Input parameters type

op

dataset {measure<scalar> _}
| component<scalar>
| scalar

Result type

result

dataset { measure<boolean> bool_var }
| component<boolean>
| boolean

Additional Constraints

If op is a Data Set then it has exactly one measure.

Behaviour

The operator has the typical behaviour of the “Operators changing the data type” (see the section “Typical behaviours of the ML Operators”).