Seth (3/13/2008)
I've had to link on a previous row in the past. I've just used self joins, i.e. joining a table on itself. In the join clause, I just put my criteria. For example:select t1.price as 'oldprice', t2.price as 'newprice' from table1 t1 join table1 t2 on t1.colnum +1= t2.colnum
Is there anything wrong with doing that? Is it less efficient or buggy?
Thanks,
Seth
That method works just fine so long as you are linking to the immediately prior ID. If, for example, you want the prior order for the same customer, your ID number is not so easily derived.
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