PL/SQL Cursors
The cursor is used to retrieve data one row at a time from the results set, unlike other SQL commands that operate on all rows at once.
Cursors update table records in a singleton or row-by-row manner.
The Data that is stored in the Cursor is called the Active Data Set. Oracle DBMS has another predefined area in the main memory Set, within which the cursors are opened. Hence the size of the cursor is limited by the size of this pre-defined area.
Cursors in PL/SQL
A Cursor in PL/SQL is a pointer to a context area that stores the result set of a query.