select('score') ->where('student_id', $studentId) ->where('semester', $semester) ->where('school_year', $schoolYear); if ($classSectionId !== null) { $builder->where('class_section_id', $classSectionId); } $result = $builder->first(); if (!$result) { return null; } $score = $result['score'] ?? null; if ($score === null || (is_string($score) && trim($score) === '') || $score === '' || !is_numeric($score)) { return null; } return (float) $score; } }