What is a database cursor?
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A cursor is SQL keyword specifying a retrieved data order.
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Cursor is acronym for Current Set Of Records and is a database object pointing to a currently selected set of records.
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A blinking vertical line that indicates the location of the next input on the display screen.
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None of the above.
To solve this question, the user needs to have some understanding of databases and their operations.
Option A: This option is incorrect. The SQL keyword that specifies the order of retrieved data is "ORDER BY" and not "cursor."
Option B: This option is correct. A cursor is a database object that points to a currently selected set of records. It allows you to retrieve and manipulate data row by row. The term "cursor" comes from the idea of a cursor in a text editor, which is a movable indicator that shows where the next action will occur.
Option C: This option is incorrect. The blinking vertical line that indicates the location of the next input on the display screen is called a "cursor," but it is not related to database operations.
Option D: This option is incorrect because option B is the correct answer.
Therefore, The Answer is: B.
A cursor is a database object that represents a private working area holding the result set of a query, letting the program fetch through those rows one at a time. It's a fundamental mechanism for row-by-row processing in PL/SQL and similar procedural SQL extensions, distinct from a simple ordering keyword or a screen UI element.