Solution to Prevent Duplicate Entry


1 Like

Hi, in fact, with a form this doesn’t work. And the solution of [noobly_channel] doesn’t delete row.
So, now the problem with form has not solution !

Sorry, what doesn’t work?

The action IF Name is not included in Name then Add Row else Delete Row … on Submit of a form
The error message is displayd, but the Row is added.
If a solution like this ACTION works with an application and does’nt work with another, I think there are a problem somewhere (I build an app test with 2 sheets, very lite and simple : only a column : Name. ) but I don’t know how to prevent duplicate entry in a form.

I’m not sure I understand, but… a question. Are you using a custom form or a native Glide form?
If you’re using native forms there is no way to prevent duplicate entries. This is because nothing is written to the table until the form is submitted, and so there is no way to detect the duplicate.

This is where custom forms come in. With a custom form, you target your input components at User Specific Columns, and the values are written to those columns immediately. You can then use those to detect duplicates before the form is submitted and take appropriate action.

Here is a concept app that demonstrates how to do it:

1 Like

In fact I use a Native Glide form, I think to use a custom form, In this exemple The Action works very well, thanks for the exemple of app.

This exemple is very clear and resolve one problem, but I have another.
My application manages a sports club. I would like to prevent members from registering several times for the same session.
I can detect duplicate cases with only one field: Name, but there are cases where husband and wife register at the same time for the same date and time.
I would therefore like to concatenate the 3 fields into one automatically, as in Excel = “name” & “first name” & “date” on a “merge” field when typing so as to obtain a field containing “Namefirst namedate” . I will then use the technique of duplicate detection on a single field.
thank you in advance for your help

It’s the same concept.
You just need to create matching template columns based on your criteria, then build a relation between the two templates. If the relation is not empty, then you have a duplicate.

Very correct, in reality I did not understand how to create template field, but now I think I understood how to get it, thanks

In my Duplicate validation, it may happen that the same event can be offered on another date and that the person has already registered for the previous event. In this case it appears as a duplicate. So I need to transfer the date of the event to the rel-dup relation field.
I thought about creating a relation with a calculated field (Template: Name-Date) in the Event sheet and also a calculated field (Template Name-Date) in the Registration sheet.
I created the relationship in the Event sheet between these two fields. But no data is displayed. While the relation Name (in Event) and Name (in registration) displays the number of rows.
I have no other ideas, maybe you have a better one of how to transfer, to relate several fields of the same sheet to another sheet? Thanks for your advices.

Do you have a screenshot of your template and relation columns?

Yes, thanks for your help

Sheet Event



Sheet Registration (Inscription)


Here a better copy screen


I think your dates are in different formats on each sheet, so the templates don’t match. On your event sheet it looks like you are using the ‘short’ date format and on the registration sheet, it’s the ‘medium’ format. For relations to work, each value that’s being compared has to match exactly. If you need to, you can create a math column in one of the sheets to convert the same date from short to medium, or vice versa. You only have to do it in one of them. Then use that math column in the template instead of the date column.

When you put a date in a template column, it becomes a string and locks in that format, so it’s no longer a date.


Thank you very much, indeed it is about the difference in format of the dates. I corrected this and everything is OK

1 Like

Hi @Wiz.Wazeer i need this for my app, this really help.
but i checked the link already expired, can i get the new one?
thank youu.

@Darren_Murphy Can you share the app that you demonstrated for duplicate entry? I am still not able to figure it out!

It is the perfect solution to this problem!

You can copy the app from the following topic: