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.
Melasma: Blotchy patches of darker color often appear on the cheeks. The woman on the right developed the brown patches while pregnant. Melasma: Signs and symptoms . Common signs (what you see) of melasma are brown or gray-brown patches on the face. These patches most commonly appear on the: Cheeks. Forehead. Bridge of the nose. Above the upper lip.