Dear List,

Could someone point me toward a solution to this update? I have a table
that might have duplicate values in the field p_h. I would like to use
an update to set another column in that table, columnn a_f, to a value of
of 'c' for all _but_one_ of the records within every set of duplicates.

In other words, after the update, all records but one within a set that
have duplicate values in p_h should have field a_f set to 'c'.

I don't care which of the duplicates get marked, I just need to have one
and only one of the duplicates left unmarked after the update.

I hope that is clear.

Thanks!

Bob Smither wrote:
> Dear List,
>
> Could someone point me toward a solution to this update? I have a
> table that might have duplicate values in the field p_h. I would
> like to use an update to set another column in that table, columnn
> a_f, to a value of of 'c' for all _but_one_ of the records within
> every set of duplicates.
>
> In other words, after the update, all records but one within a set
> that have duplicate values in p_h should have field a_f set to 'c'.
>
> I don't care which of the duplicates get marked, I just need to have
> one and only one of the duplicates left unmarked after the update.
>
> I hope that is clear.
>
> Thanks!

I would set all rows so that a_f = 'c', then use the strawberry query to
reset only the first/last record of a set to blank.
http://dev.mysql.com/doc/refman/5.0/...group-row.html

On Wed, 02 Jan 2008 15:36:40 -0600, Bob Smither
<smither78@comcast.net> wrote:

>Dear List,
>
>Could someone point me toward a solution to this update? I have a table
>that might have duplicate values in the field p_h. I would like to use
>an update to set another column in that table, columnn a_f, to a value of
>of 'c' for all _but_one_ of the records within every set of duplicates.
>
>In other words, after the update, all records but one within a set that
>have duplicate values in p_h should have field a_f set to 'c'.
>
>I don't care which of the duplicates get marked, I just need to have one
>and only one of the duplicates left unmarked after the update.
>
>I hope that is clear.
>
>Thanks!

Does your table have a primary key?
--
( Kees
)
c[_] Esistono due tipi di persone: quelle intelligenti e quelle che non lo sono.
Con le prime, non si arriva a questionare, con le altre, e` inutile farlo... (#94)

On Wed, 02 Jan 2008 23:26:56 +0100, Kees Nuyt wrote:

> On Wed, 02 Jan 2008 15:36:40 -0600, Bob Smither <smither78@comcast.net>
> wrote:
>
>>Dear List,
>>
>>Could someone point me toward a solution to this update? I have a table
>>that might have duplicate values in the field p_h. I would like to use
>>an update to set another column in that table, columnn a_f, to a value
>>of of 'c' for all _but_one_ of the records within every set of
>>duplicates.
>>
>>In other words, after the update, all records but one within a set that
>>have duplicate values in p_h should have field a_f set to 'c'.
>>
>>I don't care which of the duplicates get marked, I just need to have one
>>and only one of the duplicates left unmarked after the update.
>>
>>I hope that is clear.
>>
>>Thanks!
>
> Does your table have a primary key?

Yes it does.