OLTP is typified by a small number of rows (or records) or a few of many possible tables being accessed in a matter of seconds or less. Very little I/O processing is required to complete the transaction. For eg.
1. This type of transaction takes place when we take out money at an ATM. Once our card is validated a debit transaction takes place against our current balance to reflect the amount of cash withdrawn.
2. This type of transaction also takes place when we deposit money into a checking account and the balance gets updated.
We expect these transactions to be performed quickly. They must occur in real time.