Which mechanism allows rows of a table to be acted on at one time?

• A. View
• B. Trigger
• C. Cursor
• D. Index

Answer: (C)

Processing rows one by one is what a cursor is designed for. A cursor lets you define a result set with a query and then step through that set row by row, performing actions for the current row before moving to the next. You declare the cursor with your SELECT, OPEN it to start the result set, FETCH each row into variables, run your row-specific logic, then loop until no more rows remain, and finally CLOSE (and often DEALLOCATE) the cursor. This row-by-row control is what you need when every row requires individual processing.

In contrast, a view is just a saved query that presents data as if from a table; it doesn’t provide a mechanism to iterate or act on each row. A trigger runs automatically in response to an event like insert, update, or delete, not to manually step through rows. An index speeds up data retrieval but doesn’t perform actions on rows.