Prevent duplicate entries
Make a column refuse any entry that is already in it, such as a repeated ticket number.
In this lesson
- A rule with a custom formula can refuse a value that is already in the column.
- The formula counts how often the new entry appears.
- COUNTIF ignores capital and small letters, so sc-1047 counts as SC-1047.
Try a free lesson first
Give a column a dropdown of fixed choices, pick from it, and stop anything else from being typed.
Confident · 7 min · Free, with no sign-up
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- Skill
- Dropdowns and validation
- Stage
- Advanced
Where it sits in Dropdowns and validation
- Make a dropdown listFreeStart here
- Checkboxes8 min
- Dependent dropdowns11 min
- Prevent duplicate entriesThis lesson10 min
The steps
11 steps: 5 explanations, 4 Do this, 2 questions, then Your turn.
Try a free lesson first
Give a column a dropdown of fixed choices, pick from it, and stop anything else from being typed.
Confident · 7 min · Free, with no sign-up
Do the free lesson on your computer.
Send yourself the link and open it on a laptop or desktop.
On your computer, go tolearnford.com/go/NA3B