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.
Age spots â also called liver spots and solar lentigines â are small dark areas on your skin. They vary in size and usually appear on the face, hands, shoulders and arms â areas most exposed to the sun. Age spots are very common in adults older than 50. But younger people can get them too, especially if they spend a lot of time in the sun.