A cursor is a database object that helps in accessing and manipulating data in given result set.
The main advantage is that we can process the data row-by -row.
There are four types' cursors.
1. Static:
It always displays the result set as it was when the cursor opened.
Static cursors are always read-only.
2. Dynamic:
Dynamic cursors are opposite of static cursors. It refers all changes made to the rows in their result set when scrolling through the cursor.
3. Forward- Only:
The forward only cursor does not support; it supports
only fetching the rows serially from the start to end of the cursors.
4. Keyset-driven:
The keyset is the set of key values from all the rows that
qualified for the select statement at the time the cursor was opened.
Shashi Ray