topic Best practice to add new columns from source in Qlik Compose

Best practice to add new columns from source

RonFusionHSLLC — Fri, 14 Mar 2025 20:49:07 GMT

I've had to add columns to various dims/fact tables as the DW/DM matures or the source changes and have yet to figure out how to easily propagate the new columns end to end (source to DW to DM).

I figured out a process to update the source, add the columns to the model and the DW. That seems quite automated, most of the time.

However, I can't figure out how to get the DM to pick-up the new columns from the DW without dropping the mart entirely and re-building from scratch. Simple drop/re-create doesn't pick-up the new columns...I could be doing something wrong.

Is there an easy way to add a new column from the source and propagate that column to the DW and DM without fully rebuilding the marts?

ron

Re: Best practice to add new columns from source

Nanda_Ravindra — Thu, 26 May 2022 06:33:25 GMT

@RonFusionHSLLC

Any changes to existing data mart tables (fact/dimensions) requires a drop and recreate of the entire datamart. This is true up until our Qlik compose version 2021.8

However, starting in the 2022.5 release( currently in GA), we have a new feature wherein compose now provides auto-adjust of the tables in DataMart.

The following is available in 2022.5

-Generate & execute DDL

-Remove a column (alter table drop column…)

-Add a column (alter table add column…)

-Alter a column length / precision / scale

However the below is still not supported, but it's in our roadmap.

-Adding a dimension to a fact table (currently forces a reprocess)

-Altering data type to a different “class” (e.g. INT to VARCHAR)

You can access our 2022.5 release notes and the user guide from the below link.

https://help.qlik.com/en-US/compose/May2022/Content/ComposeDWDL/Main/DW/Guides.htm

Hope this helps!

Thanks,

Nanda

Re: Best practice to add new columns from source

Nanda_Ravindra — Thu, 02 Jun 2022 06:02:25 GMT

@RonFusionHSLLC Just checking to see if you have any follow-up questions on what I posted last week. Don't forget to mark a solution that worked for you! This will help other users find the answer.

Thanks,

Nanda

Re: Best practice to add new columns from source

RonFusionHSLLC — Mon, 06 Jun 2022 19:27:09 GMT

Sorry for late response...just getting back to this...

The auto adjust is perfect...will be upgrading asap to get that feature.

Ron