Rule Definition
The default case is executed when none of the conditions being tested for in the switch statement are met or executed. Having no default, means that there is no backup.
The cases that are "impossible" today are the ones most likely to be the causes of untraceable bugs in the future, when the impossible changes to the standard.
Remediation
Add the OTHERWISE clause for the SELECT statement not having one.
Violation Code Sample
SELECT(COND);
WHEN(A)
DO;
...
END;
WHEN(B)
DO;
...
END;
WHEN(C)
DO;
...
END;
Fixed Code Sample
SELECT(COND);
WHEN(A)
DO;
...
END;
WHEN(B)
DO;
...
END;
WHEN(C)
DO;
...
END;
OTHERWISE
DO;
...
END;
Related Technologies
Technical Criterion
CWE-478 - Missing Default Case in Multiple Condition Expression
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