Final answer:
A database transaction may include operations such as insertion, deletion, update, or query. These are critical for maintaining the atomicity and integrity of a database.
Step-by-step explanation:
A transaction in database management includes one or more database access operations. These operations can include insertion, deletion, update, or query operations. It’s essential for maintaining data integrity that all these operations are executed as a single unit, where either all of them are performed, or none are applied in case of an error. This concept ensures what’s known as atomicity in database management. An update operation alters existing information in the database, while a query operation involves retrieving information from the database without altering the data.