-- SELECT TOP 100 t.* FROM cf_FormElementPropertyValue t WHERE t.propertyId = 8 AND value LIKE '%[^a-z0-9_]%';

UPDATE cf_FormElementPropertyValue
SET value = REPLACE(
    REPLACE(
        REPLACE(
            REPLACE(
                REPLACE(
                    REPLACE(
                        REPLACE(
                            REPLACE(value, '.', '_'),
                            '-',
                            '_'
                        ),
                        '"',
                        '_'
                    ),
                    '/',
                    '_'
                ),
                '#',
                '_'
            ),
            '%',
            '_'
        ),
        '&',
        '_'
    ),
    '''',
    '_'
)
WHERE propertyId = 8 AND value LIKE '%[^a-z0-9_]%';