Question

I’ve spent hours searching the web for an answer to this question…

Here’s what I currently have:

select  *
from    order_header oh
where   tran_date = sysdate-1

Answer 1

Use:

AND oh.tran_date BETWEEN TRUNC(SYSDATE - 1) AND TRUNC(SYSDATE) - 1/86400

Reference: TRUNC

Calling a function on the tran_date means the optimizer won’t be able to use an index (assuming one exists) associated with it. Some databases, such as Oracle, support function based indexes which allow for performing functions on the data to minimize impact in such situations, but IME DBAs won’t allow these. And I agree – they aren’t really necessary in this instance.