A value of NULL indicates that the value is unknown. A value of NULL is different from an empty or zero value. No two null values are equal. Comparisons between two null values, or between a NULL and any other value, return unknown because the value of each NULL is unknown.
Skin Spots on the Face. Most causes of spots on face are harmless. They can be a variety of colors including white, red, black or brown. Common causes include cumulative sun exposure, acne, and skin tags. Keratoacanthoma (hyperkeratosis) is a lesion that grows rapidly, usually on areas exposed to the sun.
Face swelling is the enlargement or distention of the face due to fluid buildup or inflammation in the facial tissues. Swelling can occur anywhere on the face, but it is most noticeable on the lips, cheeks and eyelids. Swelling can also extend to the neck region.