I don't get any errors when running that statement. Is the server 2008 and database in the 100 compatibility mode?
or perhaps the error is for a different line?
this is what I ran:
create table #butt (type int, base_id int, lot_id int, split_id int, sub_id int, sequence_no int)
CREATE UNIQUE INDEX [IX_TESTINDEX] on #butt (TYPE, BASE_ID, LOT_ID, SPLIT_ID, SUB_ID, SEQUENCE_NO)
WITH (IGNORE_DUP_KEY = ON);
drop table #butt
Be One with the Optimizer