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.
Cellulitis: Not to be confused with cellulite (subcutaneous fat that causes dimpling of skin), cellulitis is a skin infection caused by bacteria. The bacteria can cause sudden facial swelling. Other symptoms include redness, warmth, and tenderness in the face.