Re: Merge Statement

From: Mtek <mtek_at_mtekusa.com>
Date: Tue, 3 Feb 2009 05:59:22 -0800 (PST)
Message-ID: <3db5a27f-df37-4dec-811c-7ef0a9112beb_at_r37g2000prr.googlegroups.com>

On Feb 2, 3:12 pm, ddf <orat..._at_msn.com> wrote:
> On Feb 2, 2:06 pm, Mtek <m..._at_mtekusa.com> wrote:
>
>
>
> > I have this merge statement:
>
> >      MERGE INTO rank_history_new zrh
> >        USING (SELECT v_id AS new_m_ticker, v_rec.z_rank_d AS new_rank
> > FROM dual) zrh2
> >          ON (zrh.m_id = v_id AND rank = v_rec.z_rank_d)
> >        WHEN NOT MATCHED THEN
> >          INSERT (m_id, rank, time, add_del_flag)
> >          VALUES (v_id, v_rec.z_rank_d, v_rank_date, v_add_del_flag);
>
> > It does not work 100%.  Actually what I want is to compare it with the
> > LAST entry for the v_id.  So, if I have the following.  So if there
> > are 4 entries for a given ID, I want to compare it against the last
> > entry.

David,

In this case, rank_history_new has several records for each ID. There is also a DATE on those records. When performing the MERGE, I want to compare against the record with the MAX date for that ID.

ID DATE

---

A     6/3/08
A     9/7/08
A     1/5/09     <-- Use this one in the MERGE statement.

So again, back to the merge statement, I am comparing 'rank' values, but I want to perform that compare on the record with the MAX date for that ID.

Does this help a bit in my explanation? Received on Tue Feb 03 2009 - 07:59:22 CST