Which SQL function displays "Unassigned" in results if a value is blank?

The SQL function that displays "Unassigned" in results when a value is blank is particularly well-suited for conditional logic in SQL queries. The DECODE function is used to provide conditional substitutions by evaluating an expression against a list of potential values. When it encounters a blank value (or specified condition), DECODE can replace it with user-defined output, in this case, "Unassigned."

For instance, if a query is designed to fetch values from a column that may sometimes contain null or blank values, using DECODE allows the developer to specify what should be shown in the result set instead of leaving it empty. If a specific condition is met (like the value being blank), DECODE will return "Unassigned" as the output.

While other options each serve functions in SQL, they do not directly achieve this specific output modification within a single statement in the same intuitive manner. IS NULL checks merely for null values but does not substitute the output. NULLIF functions to return null if two expressions are equal, and CASE can also achieve conditional outputs, but DECODE is the function with straightforward syntax aimed directly at transforming specific outputs through its key-value pairing approach.