11.19. Database Access with SQL
11.19.1. Cursor FOR LOOPS
The cursor FOR LOOP requires use of SQL and a PL/SQL FOR LOOP. This is a simple approach to querying the database. You can construct a cursor for loop using any valid SQL statement.
The syntax is:
FOR your_name IN (SELECT rest of SQL statement LOOP your_name.column_name is defined here END LOOP;
The following block selects all student names and the sum of their parking tickets. The LOOP temporary variable, REC, only exists for the duration of the LOOP. Within the loop we can access columns in the query through the record, REC.
BEGIN FOR rec IN (SELECT student_name, sum(amount) parking_ticket_total FROM students a, student_vehicles b, parking_tickets c WHERE a.student_id = b.student_id ...