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.
What Are Age Spots? Age spots are flat, brown, gray, or black spots on the skin. They usually occur on sun-exposed areas of the skin. Age spots are also called liver spots, senile lentigo, solar lentigines, or sun spots. Age spots are the result of an excess production of melanin, or skin pigment. Doctors donât always know why age spots develop. Skin aging, sun exposure, or other forms of ultraviolet (UV) light exposure, such as tanning beds, are all possible causes. Youâre most likely to develop age spots on the areas of your skin that receive the most sun exposure, including: your face.