Prevent Duplicate entries in powerapp

[Anonymous]

I have created power app but I want user should not enter duplicate entry, if he tries then he should get error message.

Lookup & Countrows tried several time but not working.

Need help

[Anonymous]

@AARON_C This is my code

Set(VarChk , LookUp('Stamp/Mount Request','Ticket No.'= Value(DataCardValue11.Text))); Blank(); Notify("This Ticket No. is already exists.", NotificationType.Error) ; SubmitForm(EditForm1);

[AARON_C]

@Anonymous 

Could you please tell me where this code is.

Also, you initially had the column 'Question 1' (number column) in your lookup, now you have 'Ticket No.'. What type of column is this?

Secondly, you have a random, Blank(); in your formula. I don't know what this is doing.

Thirdly, you are just setting a variable, then notifying the user, then submitting the form. You have no logic at the moment to say when to notify the user.

[Anonymous]

@AARON_C  This code I have written for submit button.

I have changed the code now but it's showing error for every new entry & accepting the same

Now please suggest me necessary changes.

[AARON_C]

@Anonymous 

You still need an IF statement. Try this:

If(
  'Ticket No.'.Text = LookUp('Stamp/Mount Request', Question1=Value(DataCardValue11.Text).Question1,
  Notify("Error"),
  SubmitForm(EditForm1)
)

Please tick Accept as solution if the answer is useful.

Thanks,

@AARON_C 

[Anonymous]

@AARON_C  Instead of ticket no I have written datacardvalue11 bcoz it's column name of ticket no & ticket no isn't recognized name popping up

[AARON_C]

@Anonymous 

Sorry, my bad. Yes, it should be DataCardValue11.Text and not 'Ticket No.'.Text.

You need it to be = and not a , after the first DataCardValue11.Text

[Anonymous]

Bro after using = it's now showing incompatible type of comparison😪

[AARON_C]

@Anonymous 

Okay, so what is it comparing? Text and Record?

If that is the case, that is because you need to add which column you want to display for the record that got looked up. You have removed the column after the lookup function and also removed the condition on what record to look up. I did not tell you to remove this, only to swap the , to a = sign.

I do not know what your data source looks like so when I added .Question1 after the look up function that was me guessing the column name. It is probably 'Ticket No.'

[Anonymous]

@AARON_C 

Error message is This type's can't be compared=Text,  _Min.

Stamp/Mount Request is name of my Share point list which is my data base & in that Ticket no. is 1 column which I want to get looked up & prevent duplicate entries.

& Question1 is data Field name 

[AARON_C · Accepted solution]

@Anonymous 

Okay starting from the beginning again and double checking I am understanding everything right.

• Stamp/Mount Request is the name of your list
• Ticket No. is a column in Stamp/Mount Request
  • What type of column is this?
• DataCardValue11 is the Text Input control for users to enter in a Ticket No

What you are wanting is, on select of a button, you want to check, is if a user entered in a Ticket No in DataCardValue11, this value is not already in the Stamp/Mount Request list.

If it is in the list already, notify the user.

If it is not in the list, submit the form.

We are not using Question 1. I am not sure why you added this in before in your previous messages.