Cursors in SQL:
A cursor is a database object that help in naccessing and manupulating data in given result set.
The main advantage is that we can process the data row-by -row.
There are four types cursors.
It alwys displays the result set as it was when the cursor opened.
statis cursors are always read-only.
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 cursors does not support ; it supports
only frtching the rows serially from the start to end of the cursors.
The keyset is the set of key values from all the rows that
qualified for the slect statement at the time the cursor was opened.