topic Reduce reload time in App Development

Reduce reload time

ArunaVeerappan — Mon, 06 Oct 2025 19:48:39 GMT

How do I reduce app reload time when working with large data sets?

Re: Reduce reload time

robert_mika — Tue, 07 Oct 2025 02:19:24 GMT

Try if you have not doing this yet:

- Instead of reloading the entire dataset every time, load only new or changed records.

WHERE LastModifiedDate > $(vLastReloadDate)
Store vLastReloadDate in a variable or QVD

-Split logic into Extract → Transform → Load (ETL) layers

- Avoid nested transformations during reload

- Limit the number of fields during load:

qlik
LOAD ID, Name, Date FROM ...;
Drop unused fields immediately

- Avoid LOAD * unless absolutely necessary

- Use WHERE Clauses and Filters
Filter data at the source:

SQL SELECT * FROM Orders WHERE OrderDate >= '2023-01-01';
Reduces volume before it hits Qlik

- Avoids unnecessary memory usage

- Optimize Joins and Keys
Use numeric keys for joins (faster than strings)

Re: Reduce reload time

Vegar — Tue, 07 Oct 2025 04:56:27 GMT

In addition to @robert_mika 's list, I would also mention the speed differences between fetching data from qvd files in an optimised or a non-optimised load.

I think Bitmetric with @barryharmsen have a pretty good explanation of optimised load in this blog post from 2022. https://www.bitmetric.nl/blog/qlik-optimized-load/