Is there a way to identify an entry as a duplicate in the same column. For
instance, if 4310011192 is already entered in the column and I enter it
again, an error will result, informing the user "Duplicate entry". I know you
can do this in ACCESS by virtue of the primary key, but don't know how to do
it in Excel.

Let's say your data in Column A
Select column A:A
Go to menu, Data Data Validation under Allow: select Custom under
Formula: =COUNTIF(A:A,A1)=1



"Jan Buckley" wrote:

Is there a way to identify an entry as a duplicate in the same column. For
instance, if 4310011192 is already entered in the column and I enter it
again, an error will result, informing the user "Duplicate entry". I know you
can do this in ACCESS by virtue of the primary key, but don't know how to do
it in Excel.

One way via data validation
Assuming data will only be entered manually* down col A ..
*as any copy-pasting, or dragging down a cell with input in it will override
the validation

Select col A (click on the col header "A")
Click Data Validation
Allow: Custom
Formula: =COUNTIF($A:$A,A1)<2
Click OK

Test it out ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Jan Buckley" wrote:
Is there a way to identify an entry as a duplicate in the same column. For
instance, if 4310011192 is already entered in the column and I enter it
again, an error will result, informing the user "Duplicate entry". I know you
can do this in ACCESS by virtue of the primary key, but don't know how to do
it in Excel.

I don't want to have to filter to find the dupes. I want them identified upon
entry.

"Teethless mama" wrote:

Let's say your data in Column A
Select column A:A
Go to menu, Data Data Validation under Allow: select Custom under
Formula: =COUNTIF(A:A,A1)=1



"Jan Buckley" wrote:

Is there a way to identify an entry as a duplicate in the same column. For
instance, if 4310011192 is already entered in the column and I enter it
again, an error will result, informing the user "Duplicate entry". I know you
can do this in ACCESS by virtue of the primary key, but don't know how to do
it in Excel.

Max, thanks so much! Works like a charm.

"Max" wrote:

One way via data validation
Assuming data will only be entered manually* down col A ..
*as any copy-pasting, or dragging down a cell with input in it will override
the validation

Select col A (click on the col header "A")
Click Data Validation
Allow: Custom
Formula: =COUNTIF($A:$A,A1)<2
Click OK

Test it out ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Jan Buckley" wrote:
Is there a way to identify an entry as a duplicate in the same column. For
instance, if 4310011192 is already entered in the column and I enter it
again, an error will result, informing the user "Duplicate entry". I know you
can do this in ACCESS by virtue of the primary key, but don't know how to do
it in Excel.

Delighted, Jan !
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Jan Buckley" wrote in message
...
Max, thanks so much! Works like a charm.