Hi Subbu, A Qualifier allows a field to maintain different type of data.For example ,if 'date' is a field with quilifier ,then that date field can hold a) creation date b)sold date c)delivery date etc....
Why Does My Mucus Change Color? If you've ever stopped to look at the contents of the tissue after you've blown your nose, you may have noticed that your mucus isn't always perfectly clear. It may be yellow, green, or have a reddish or brownish tinge to it. What do those colors mean? You might have heard that yellow or green mucus is a clear sign that you have an infection, but despite that common misperception, the yellow or green hue isn't due to bacteria. When you have a cold, your immune system sends white blood cells called neutrophils rushing to the area.
1 Therefore, if you are coughing up phlegm that is green in color it is a sign that your body has been infected. 2  The mucus turns green on color because of the presence of an enzyme that is known as myeloperoxidases (MPO). 3  This enzyme is green in color.ucus, which is a form of phlegm, helps protect and lubricate the body internally. It is essential for keeping the tissues in the body moist. It also keeps dirt, bacteria, dust, airborne allergens and pollen from entering the lungs, as you breathe.