delete is extremely slow

[Emi Lu <emilu@xxxxxxxxxxxxxxxxx>]

Hello,

Tried to run:

delete from tableA where id <600000;

It is extremely slow.

id is integer and also the primary key. tableA has around 90000 records.

(I do not want to run truncate since I have some foreign key constraint 
setup based on tableA. Besides not all data I want to delete; only part 
of them).

Thanks