topic Re: NOT NULL constraint violated during initial load in Qlik Replicate

NOT NULL constraint violated during initial load

LaCools — Thu, 20 Mar 2025 12:37:48 GMT

I'm using Oracle as source, with a logstream set up.
Targets are azure sql server (managed instance) and databricks (delta).
qlik replicate version 2024.5.0.480

When loading a certain table, i'm getting the error:

[DELTA_NOT_NULL_CONSTRAINT_VIOLATED] NOT NULL constraint violated for column: XXX.

The source was recently (several days ago) adjusted. The column went from required, to optional. Meaning 'not null' -> nullable. From that day, the new values in that column are empty.

In our source endpoint (oracle), the column is nullable. When qlik creates the table in both of the targets, the column is NOT nullable.

In the past, i've had this issue as well, but never got an answer. Now i wonder how this can happen, and what the fix is.

Re: NOT NULL constraint violated during initial load

john_wang — Tue, 25 Mar 2025 13:10:18 GMT

Hello @LaCools ,

Welcome to Qlik Community forum and thanks for reaching out here!

I did a quick test here, Oracle source replicate to SQL server target. the source table was created by:

create table testnull (id integer not null primary key,name char(20) not null, notes varchar2(20));

So far only column "notes" is nullable. Qlik Replicate create the target table with the correct nullable properties (no additional transformation was defined), this is the target side table:

I used Replicate 2024.5.0.563.

Hope this helps.

John.

Re: NOT NULL constraint violated during initial load

LaCools — Wed, 26 Mar 2025 16:03:26 GMT

My problem that i described happens when you try to alter the 'name' column to also become nullable.

Qlik doesn't replicate that change.

Re: NOT NULL constraint violated during initial load

john_wang — Wed, 26 Mar 2025 23:14:36 GMT

Hi @LaCools ,

You are right. This DDL change of NULLABLE property is not replicated in current versions. If this is a feature you would like to see, please submit a request here which goes to our Product Management team. Other users will have the opportunity to vote on it to increase the chances at adoption and to set the priority: https://community.qlik.com/t5/Ideas/idb-p/qlik-ideas

Regards,

John.

Re: NOT NULL constraint violated during initial load

LaCools — Thu, 27 Mar 2025 08:00:19 GMT

It says the page is no longer in use. Can i create a ticket in another way?

Re: NOT NULL constraint violated during initial load

john_wang — Thu, 27 Mar 2025 08:04:13 GMT

Hi @LaCools ,

sorry for that. Would you please try this page:
https://community.qlik.com/t5/Ideation/ct-p/qlik-product-insight

Regards,

John.

Re: NOT NULL constraint violated during initial load

Gunjansingh1 — Wed, 04 Jun 2025 09:37:28 GMT

We are having similar issue. I'm using IBM DB2 for iSeries as source and Targets are ADLS and databricks lakehouse (delta). qlik replicate version Nov 2024 (2024.11.0.177

what was the outcome. Any inputs would help us resolve the issue.

Re: NOT NULL constraint violated during initial load

LaCools — Wed, 11 Jun 2025 12:48:39 GMT

The people at Qlik believe this is a 'feature' not a bug.

You can vote on this page to make this request noteworthy.

The only workaround at this moment is to remove the table from the task to clean the metadata and reload it completely.