The SQL NULL is the term used to represent a missing value. A NULL value in a table is a value in a field that appears to be blank. A field with a NULL value is a field with no value. It is very important to understand that a NULL value is different than a zero value or a field that contains spaces.
Someone with red spots on their tongue may be suffering from geographic tongue, according to Mayo Clinic. Other causes of red spots on the tongue include folic acid and vitamin B-12 deficiencies and scarlet fever, WebMD states. Continue Reading.
Causes. White tongue is the result of an overgrowth and swelling of the fingerlike projections (papillae) on the surface of your tongue. The appearance of a white coating is caused by debris, bacteria and dead cells getting lodged between the enlarged and sometimes inflamed papillae.xamples of conditions associated with white patches or other discolorations of your tongue include: 1  Use of certain medications, such as prolonged use of antibiotics that may bring on an oral yeast infection.