We all know that data validation is a very useful feature in Excel. You can use data validation to create a drop-down list in a cell and limit the values user can enter. But, do you know that you can use data validation in a multitude of ways to prevent users from entering wrong data?
Here is a practical application: Prevent users from entering duplicate values in a range of cells.
For eg. you are making an invoice. Wouldn’t it be cool if Excel prompted you when you enter a duplicate line item so that increase the item quantity instead of repeating it.
Here is a 3 step tutorial to do just that.
Step 1: Identify the range of cells where you want only unique values to be entered
This is simple. All you have to do is find the range where you want to control the user input. Lets say the range is B4:B11
Step 2: Set up Data Validation to prevent duplicate entries
Select the range (B4:B11) and go to data validation (Excel 2007: Data Ribbon > Data Validation, or press ALT+AVV)
Now, specify the validation type as “Custom”, this will allow us to use formulas to check for valid data. In our case, we need check if a particular entry is duplicated in the range B4:B11. This can be easily done using COUNTIF formula [learn COUNTIF Formula in plain English].
Go to the formula field and type the countif formula like this: =COUNTIF($B$4:$B$11,B4)<=1
Also, you can set up the “Error Alert” so that you can show a custom message when a duplicate value is typed, like “You have already added that product” message.
Once you set up error message, it will show up like this:
Step 3: Sit back and Relax
The third step is all too familiar. Now that you have prevented duplicate entries in your spreadsheets you can sit back and relax. May be read a few more spreadcheats.
More kickass stuff on data validation (and working with duplicates) using excel
There are a ton of useful articles on the site related to data validation and working with duplicates using excel. Here is a sample. Get started and learn something useful today.
- Data Validation Tricks in Excel [with downloadable tutorial]
- Remove Duplicate Values from a Range in Excel
- Using Array formulas to find if a list has duplicates
- Working with duplicate items in Excel [several examples]
- Examples & Articles on Excel Data Validation
This post is part of our spreadcheats series (yes, the series is still going after one year 😛 )
30 Responses to “Great News: Chandoo becomes MVP”
Congratulations! It's well deserved. 🙂
This is amazing. Hearty congratulations and a rocking new year ahead!!!
Congrats! I have learnt alot from your site... and the most important is learning how to achieve the most with the simplest concepts.
Thanks for the excel calendar. Is it possible to get a simple big fonted calendar printable on an A4 size paper without any distracive notes or visuals? BTW, I have already signed up for your newsletter. With warm regards and
Gratefully yours
50+ year old CHarish.
Hey Chandoo,
Great to hear that. Congratulations! The best new year gift, I would say. Keep it up, u've been doing extraordinary work for the excel users community.
Regards,
Pankaj Verma
Congrats dude... fantastic news!
congratulations! your site is great, this is well deserved
Rich
I recently found your site, I visit many. The tips that you provide are in the top 1% of all the sites I visit. Keep on Excelling.
Arnold
South Africa
Congratulations, Chandoo! That's a great way to start the year and make the PHD even better.
Congratulations, Chandoo.
Your site is one of most useful on the net. Happy new year and lot of ideas you will present for us.
Congrats.
Just read your name in an email from Abhishek. Well deserved.
Congratulations, and Happy New Year.
Greetings from Rio de Janeiro my friend! You trully deserve it!
Nive way to start 2009! Keep up the good work!
FC
That was quite forseeable , so you have now really got your PhD in excel.
Anyways Chandoo you have made excel a real Fun doo
I will like you to write some more on INDEX and MATCH function in near future.
@Hey Chandoo ! Congrates....
Ab to treat mangta hai !
Well deserved Chandoo!!
Congrat's!! Very well deserved 🙂
i always browsed mr.excel and used to see MVP writtne below names of people who used to solve queries in excel forum there......i just used to admire as to what they have special in them that they are MVP......
but now i got my answer...............u deserve it man..........
@All: thanks everyone 🙂
Congratulations Chandoo, nice job!
Chandoo,
A well deserved recognition and a good start to the New Year. Continue your good work.
Subbu
Many Congratulations.
You deserve a Ph.D. 🙂
congrats.....
Congrats dude. Rock on!
[...] charting community in 2007 and has been growing strongly ever since. In year 2009, I have received the MVP award from Microsoft. Just few days back I have become a dad [...]
Respected sir,
I am impressed!.... Good job done.. Keep it up...
Sir, How to be a MVP certified person. What level of knowledge is required for it? send me links if possible.
Please reply...
Regards,
Dipak Khalasi.
Dipak -
The first thing you need to cultivate is the ability to search the web effectively. You could start by Googling "Microsoft MVP".
[...] boy and girl which has been made hectic and incredibly fun ever since to their life.He has been awarded MVP status in 2009 by Microsoft(and renewed in 2010,2011 & 2012).His MVP profile is here.If you want to contact him direct then [...]
Congrats Chandoo!!
[…] Chandoo becomes MVP […]