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.
1 Foods with very high acid content may also cause pimples on tongue. 2  Pimples on tongue can be a result of some kind of injury to the tongue caused by scraping or biting.  Oral thrush or oral candidiasis â a yeast infection â can also cause pimples on tongue.