Null handling on Database Delete Node

Hi everyone,

I’m trying to use the Database Delete node to delete certain rows on a database based on the input of two columns.

As I understand, the node checks the value of each of the input columns, and if finds a match on the database deletes the row.

It works well 95% of the times, however, when it comes to assessing null values, the node doesn’t seem to read them properly.


I have two columns such as : Product_ID, Product_Description.

1- Product ID = 123 Product_Description is null
2- Product ID = 123 Product_Description = “Abc”

Both rows are available in the database, however only row 2 will be deleted.

Thanks for your help!

Null compare to Null is uncertainty. Null can not be used for comparison. Use IsNull(Product_Description, ‘’) function on both side of the comparison.

To be able to use IsNull() I guess I would need to bring the data into Knime.

I will replace Nulls with ‘NA’ on the DB so I can perform the operation with the Delete node.

It would be great if we had an “Upsert” node, so we can easily implement SCD type1 updating existing records + insert new ones.