Cannot put a NULL value into an SQL DB column using Patch()

[VictorSotnikov]

I have a canvas Power App that is connected to a SQL Server table MyDB with a column MyColumn:

            MyColumn [nvarchar](255) NULL

In the App I have the following code in OnChange property of a Dropdown control:

          Patch('MyTable',ThisItem,{MyColumn:Blank())

This does not work – the MyColumn does not acquire NULL after the code is executed.

How can I fix it?

[poweractivate]

@VictorSotnikov 

Can you check if turning on the formula-level error management setting helps with this?

1. Click Settings

2. Click Upcoming Features

3. Toggle the Formula-level error management setting to On

Then just close the modal, see if it works.

See if it helps @VictorSotnikov 

[VictorSotnikov]

Yes - it has helped.

Do you know the answer - why this has helped?

[poweractivate]

@VictorSotnikov 

No, I do not know why this has helped. 

I suspect it is some internal reason.

I really don't know the reason though.

@v-jefferni @v-xiaochen-msft @v-bofeng-msft do either of you know the reason? I do not know the reason.

[v-jefferni]

Hi,

Please refer to the blog:

New Experimental Feature: Error Handling and Writing Null values to databases | Microsoft Power Apps

Best regards,

[poweractivate · Accepted solution]

Thank you @v-jefferni , I think I might understand the reason better now based on that link you provided.

Did it help you @VictorSotnikov to understand the reason ?