Introduction to Transactions. A transaction is a logical unit of work that contains one or more SQL statements. A transaction is an atomic unit. The effects of all the SQL statements in a transaction can be either all committed (applied to the database) or all rolled back (undone from the database). A transaction begins with the first executable SQL statement.
When you get sick and have an irritating cough, you probably just want it to go away. There are dozens of medications on the pharmacy shelves that promise to quiet the cough, but do they actually work? There are two different types of over the counter cough medications - expectorants and suppressants. They work very differently and which one you should take depends on the type of cough you are experiencing. Expectorants are a class of cough medicine that help to get mucus out of your lungs. They thin the mucus and help you cough it out more easily. Expectorants are useful when you have thick congestion and you can't cough it up on your own.
Several types of medications are used to treat allergy symptoms. Here's more information. Allergy medications are available as pills, liquids, inhalers, nasal sprays, eyedrops, skin creams and shots (injections). Some allergy medications are available over-the-counter, while others are available by prescription only.Here's a summary of the various types of allergy medications and why they're used.ills and liquids. Oral decongestants relieve nasal and sinus congestion caused by hay fever (allergic rhinitis). Many decongestants, such as pseudoephedrine (Sudafed, Afrinol, others), are available as over-the-counter drugs. A number of oral allergy medications contain a decongestant combined with an antihistamine.