Dynamics 9, empty required fields accepted; Blank() vs ""?

[SaWu]

Please be so kind as to read my full post before responding.
My actual questions are at the bottom of the post.
The required attribute of datacards in the form is not relevant to my question.

I do already have a workaround, not a solution, for my problem and have listed it at the botto just in front of my actual questions.

Thank you for your consideration.

I am using PowerApps to connect to Dynamics 9.0.2.1719 with Common Data Service.
I have to deal with a custom entity with 3 required fields (required in the the entity) kk_company, kk_lastname, kk_firstname and guid kk_exhibition_leadid.
I have not yet been able to reproduce my error with another PowerApp for a standard entity with standard fields for testing purposes.
Hence, all my code examples refer to these field names, etc.
For various reasons, I cannot directly use SubmitForm but am using Patch after making some adjustments to the submitted record.

In one app that I have already spent too much time on, the checks for the required fields have suddenly stopped working.
Leaving the required fields empty and submitting via Patch succesfully enters the record into the CRM database.
Even a completly blank record is accepted.

Upon some testing I have been able to reduce my problem to the following minimal example:

1. Open a standard Common Data Service Template for the Table.
2. Choose the fields kk_company, kk_lastname, kk_firstname as Fields of EditForm1
3. Rename the Text Input of these fields to CompanyInput, LastnameInput, FirstnameInput
   
4. Change the OnSelect action of the submit button to
   

   Patch('Messe-Erfassungen', {kk_exhibition_leadid: Blank()}, {
       kk_company: CompanyInput.Text,
       kk_lastname: LastnameInput.Text,
       kk_firstname: FirstnameInput.Text
   })

   
5. Play the PowerApp and try to submit an empty record (required fields not filled!)

The expected behaviour is that the empty record is not accepted:

If I create a new PowerApp following these steps I get the expected behaviour.

However, in the PowerApp that I have been developing for quite some time, (recreating) the same Form with the same fields and attributes and code suddenly started accepting these empty records into the CRM:


After some testing I am now assuming the crux of the issue is the difference between Blank() and "".
In both my old and new apps the following code produces the expected behaviour of records with missing required fields not being accepted:

Patch('Messe-Erfassungen', {kk_exhibition_leadid: Blank()}, {
    kk_company: Blank(),
    kk_lastname: Blank(),
    kk_firstname: Blank()
})

However, in both my old and new apps the following code produces the unexpected behaviour of records with missing required fields being accepted and even yielding basically empty records in the CRM:

Patch('Messe-Erfassungen', {kk_exhibition_leadid: Blank()}, {
    kk_company: "",
    kk_lastname: "",
    kk_firstname: ""
});

As a workaround, in both my old and new apps the following code produces the expected behaviour of not accepting records with empty required fields:

Patch('Messe-Erfassungen', {kk_exhibition_leadid: Blank()}, {
    kk_company: If(IsBlank(CompanyInput.Text), Blank(), CompanyInput.Text),
    kk_lastname: If(IsBlank(LastnameInput.Text), Blank(), LastnameInput.Text),
    kk_firstname: If(IsBlank(FirstnameInput.Text), Blank(), FirstnameInput.Text)
})

My actual questions are:

• Why does NewForm set yet unfilled fields to, apparently, "" in my old (for some reason bugged?) PowerApp and Blank() in a new freshly created PowerApp?
• How can I "reset" my original App to the expected behaviour?
• Why does Dynamics even accept "" in required fields in the first place?
  Or am I missing some setting in Dynamics that allows ""?
  
  

Thank you for your consideration.

[v-xida-msft]

Hi @SaWu,

For your first question, I think you have some misunderstanding in "" and Blank(). The "" is not equal to Blank(). The Blank() function is used to create a blank value (a placeholder for "no value" or "unknown value"), but the "" represents a empty string text value.

The "" represents a string text value, but there is no character within this string text. You could consider take a try to add a Label control within an app, set the Text property to following formula for checking if "" is equal to Blank():

If(Blank()="",true,false)

the above formula would return false.

For your second question, I agree with the last solution that you provided almost. You could consider take a try to check if the corresponding fields (TextInput controls) are empty, if yes, provide Blank() for the corresponding fields, otherwise, provide corresponding input values.

In addition, you could also check if the corresponding TextInput controls are empty before executing the Patch function. Please modify your formula as below:

If(
  IsBlank(CompanyInput.Text)||IsBlank(LastnameInput.Text)||IsBlank(FirstnameInput.Text),
  Notify("The required fields must be populated with values",NotificationType.Warning),
  Patch(
     'Messe-Erfassungen', 
     {kk_exhibition_leadid: Blank()}, 
     {
      kk_company: CompanyInput.Text,
      kk_lastname:LastnameInput.Text,
      kk_firstname: FirstnameInput.Text
     }
   )
)

For your third question, please check my response for your first question as above. In addition, I think you have some misunderstanding within SubmitForm function and Patch function.

The SubmitForm function would automatically check for validation issues with any field that's marked as required or that has one or more constraints on its value before submitting any changes. Please check here for more details.

Best regards,

Kris

[SaWu]

Thanks for reading and replying.

I think I do understand the difference between SubmitForm and Patch.
Since I think you need more details on what I'm doing, I use Patch because it allows more control and it also allows selections in MultiSelect OptionSet or OptionSet field to be unset.
SubmitForm does not seem to accept changing selections to "nothing selected".
You have already already read my inqury about this here:
https://powerusers.microsoft.com/t5/General-Discussion/PowerApps-Dynamics-9-MultiSelect-Option-Set-e...

I also do understand the difference between "" and Blank().
They are not the same but they are close:

Also, as shown in my original question, Dynamics apparently accepts "" in Required fields but does not accept Blank() in required fields.

This is why my assumption is that the unwanted empty records created in the Dynamics are caused by submission of "".

Normally, trying to create a new record with a Form and NewForm seems to reset Inputs to Blank().
Trying to SubmitForm or Patch then yields expected "Required field empty" errors.

In my "stuck" App, something else happens.
Trying to SubmitForm or Patch then yields unexpected empty records in the CRM.

Let me reiterate my question:
- Shouldn't there be a guarantee that all Form Inputs, for fields with no default set in the CRM, are reset to Blank() after calling NewForm?