Forum Discussion
Resolver IIWhich types of columns are considered non-nullable? (Mashup Error 104100)
Hi all,
for a Gen2 Dataflow I am getting the almighty error 104100 regarding non-nullable columns. I tried now many things, in particular replacing null values in custom columns. So far I did not manage to run the flow successfully (destination Lakehouse table).
Can someone tell me, which types of columns are considered non-nullable in general?
it depends on how the table was created. If you are using Dataflow Gen2 to create it, then by default it sets all columns to be non-nullable meaning that all your columns require to comply to this. If you create the table using other tools and you just use Dataflow Gen2 to put the data in that table, then it'll rely on what you defined as nullable and non-nullable fields during the creation of that table.
We're actively working on making the default option to be nullable, but will also pass this feedback to the owner of this feature.
You'd need to make sure that all your fields comply with the non-nullable aspect. Not just the custom columns.
You can also take a look at the new features that were released today as well as a section that talks about the non-nullable aspect:
Dataflows gen 2 data destinations and managed settings | Microsoft Fabric Blog | Microsoft Fabric
6 Replies
- miguel
Community Admin
non-nullable columns are columns that can't contain a null value. You could replace "null" with a value of your choice to make sure that your columns don't contain null values
JayJay11Thank you miguel this I understand. But which types of columns can't contain null values? So far I figured that custom columns cannot contain null values.
Second question: Is there a way to make a column nullable in the Lakehouse table?
And last but not least: Is there a way to make the error message telling us users which columns are affected? Otherwise it is try&error really.
- miguel
it depends on how the table was created. If you are using Dataflow Gen2 to create it, then by default it sets all columns to be non-nullable meaning that all your columns require to comply to this. If you create the table using other tools and you just use Dataflow Gen2 to put the data in that table, then it'll rely on what you defined as nullable and non-nullable fields during the creation of that table.
We're actively working on making the default option to be nullable, but will also pass this feedback to the owner of this feature.
You'd need to make sure that all your fields comply with the non-nullable aspect. Not just the custom columns.
You can also take a look at the new features that were released today as well as a section that talks about the non-nullable aspect:
Dataflows gen 2 data destinations and managed settings | Microsoft Fabric Blog | Microsoft Fabric