Getting past days data based on DATE data type column

Question

I am trying to extract last 2 days data using date data type column with below query,
select * from tbl
where col < col -2;
this is not showing me any data. please help where i am making mistake. guide please. thx

Answer 1

Hi,
When you say "last 2 days" do you mean the 48 hours right before run-time?
If so, you want to compare col to SYSDATE:
select  *
from    tbl
where   col  >  SYSDATE - 2
and     col  <= SYSDATE
;If you mean the "last 2 days" before some other event, then replace SYSDATE with that date in both places above.
If you were trying
where   col  >  col - 2then you should have been getting all rows that have a non-NULL col. If you were getting no results, then something is very wrong.
I hope this answers your question.
If not, post a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all the tables involved, and the results you want from that data.
If the results depend on when you run the query, then give a couple of different examples, with the run-time. for example "If I run this at 03:00:00 on July 1, 2012, then I should get ... but if I run ir at 15:00:00 on July 1, 2012, then the results should be ...".
Explain, using specific examples, how you get those results from that data.
Always say what version of Oracle you're using.
See the forum FAQ {message:id=9360002}