Optimizers Are Not Perfect - Relational Database Index Design and the Optimizers - page 264

SQL 14.8

DECLARE CURSOR141 CURSOR FOR
SELECT LNAME, FNAME, CNO
FROM CUST
WHERE (LNAME = :LNAMEPREV
AND
CNO > :CNOPREV)
OR
(LNAME > :LNAMEPREV
AND
LNAME <= :LNAMEMAX)
ORDER BY LNAME, CNO
WE WANT 20 ROWS PLEASE

Restriction: You may not remove the ORDER BY.
Hint: The WHERE clause may contain the operator NOT, but NOT makes the
predicate difficult for the optimizer (no matching).
14.2. List the most common pitfalls for your current optimizer.