Problem when exporting specific columns


I have a problem when exporting specific columns that contain null values

is there a condition which allows to export specific columns which contain null values ​​in a specific column export

Help me please

I've just tested this and it worked normally:



@enchev, @korchev

in the first part I exported the columns that I want to export:

when I click on the export button the message 500 which appears :

but for the ODATA I see that the data is recovered from the base :

can you help me please

The code of the writer is part of your app and you can debug it to see what is null.

I already have the columns which are empty when I remove them from the selection the problem does not occur