What is cursors?

What is cursors?
Cursor is a database object used by applications to manipulate data in a set on a row-by-row basis,
instead of the typical SQL commands that operate on all the rows in the set at one time.

In order to work with a cursor we need to perform some steps in the following order:
Declare cursor
Open cursor
Fetch row from the cursor
Process fetched row
Close cursor
Deallocate cursor

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