How to eliminate duplicate entries

If I import files into excel how can I ensure that no duplicates are imported?
Many thanks
Tara

See;

http://www.cpearson.com/excel/duplicat.htm

While this is helpful info, with a file of 23,000 names and addresses, there
were well over a thousand dups that showed up, some with 3 or more dups.
Since all of the duplicate data including the first occurence had a
"Duplicate" in the next column, I used autofilter to list all the dups, but
I still had to delete the actual dups manually. Also, in excel 2000 the
method mentioned at cpearson to add "duplicate" to an adjacent column so you
could autofilter the results caused my computer to repeatedly crash until i
did smaller sections of data at a time.

What i would like to know is : how do you leave the first occurence of the
data, and mark only the dups (trips etc). The suggestions in this forum mark
all occurences of the duplicate data. I would like the first occurence of the
same address to be a 0 and each succeeding occurence to be a 1 or greater so
that i can autofilter and then delete everything over 0, not have to delete
the rows out myself.

"[email protected]" wrote:

> See;
>
> http://www.cpearson.com/excel/duplicat.htm
>
>

I think you'll find that deleting a bunch of rows in an autofilter goes much
more smoothly if your data is sorted to group the rows to be deleted.

If you have to have your data in the current sorted order, add another helper
column. And put the row number in each cell in that column.

I use
=row()
then copy down
edit|copy
edit|paste special|values

Then I do all the duplicate formula stuff. Then I convert that column to
values, too (just to make things quicker).

Then I sort by that duplicate indicator column and delete the duplicates. Then
remove the filter, and finally sort by that helper (row indicator) column (and
really finally), delete that helper column.

bob z wrote:
>
> While this is helpful info, with a file of 23,000 names and addresses, there
> were well over a thousand dups that showed up, some with 3 or more dups.
> Since all of the duplicate data including the first occurence had a
> "Duplicate" in the next column, I used autofilter to list all the dups, but
> I still had to delete the actual dups manually. Also, in excel 2000 the
> method mentioned at cpearson to add "duplicate" to an adjacent column so you
> could autofilter the results caused my computer to repeatedly crash until i
> did smaller sections of data at a time.
>
> What i would like to know is : how do you leave the first occurence of the
> data, and mark only the dups (trips etc). The suggestions in this forum mark
> all occurences of the duplicate data. I would like the first occurence of the
> same address to be a 0 and each succeeding occurence to be a 1 or greater so
> that i can autofilter and then delete everything over 0, not have to delete
> the rows out myself.
>
> "[email protected]" wrote:
>
> > See;
> >
> > http://www.cpearson.com/excel/duplicat.htm
> >
> >

--

Dave Peterson

bob

How about using Advanced Filter>Unique records only and Copy to a new location
like a new sheet.

For more on this see Debra Dalgleish's site

http://www.contextures.on.ca/xladvfilter01.html


Gord Dibben Excel MVP

On Tue, 1 Mar 2005 18:51:01 -0800, "bob z" <[email protected]> wrote:

>While this is helpful info, with a file of 23,000 names and addresses, there
>were well over a thousand dups that showed up, some with 3 or more dups.
>Since all of the duplicate data including the first occurence had a
>"Duplicate" in the next column, I used autofilter to list all the dups, but
>I still had to delete the actual dups manually. Also, in excel 2000 the
>method mentioned at cpearson to add "duplicate" to an adjacent column so you
>could autofilter the results caused my computer to repeatedly crash until i
>did smaller sections of data at a time.
>
>What i would like to know is : how do you leave the first occurence of the
>data, and mark only the dups (trips etc). The suggestions in this forum mark
>all occurences of the duplicate data. I would like the first occurence of the
>same address to be a 0 and each succeeding occurence to be a 1 or greater so
>that i can autofilter and then delete everything over 0, not have to delete
>the rows out myself.
>
>"[email protected]" wrote:
>
>> See;
>>
>> http://www.cpearson.com/excel/duplicat.htm
>>
>>