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.
Melanoma can be more serious than the other forms of skin cancer because it may spread (metastasize) to other parts of the body and cause serious illness and death. Spots suspicious for melanoma usually show one or more of the following symptoms and signs (the ABCDs): Asymmetry, Border irregularity, Color changes or too many colors in one mole,