topic Re: Chart failed to load in QlikView

Chart failed to load

santhosh_k_n — Wed, 20 Jan 2016 10:41:23 GMT

Hi All,

I facing an issue while displaying data in a chart. Am using aroung 8 straight table sharts in my dashboard and 2 chart are taking long time to load which in the end making the dashboard hang.

The calculated time and the memory of the respective chart is aroung 5000 and 6mb(2lakh+ records)

Can any one suggest how to handle.

Regards,

Re: Chart failed to load

miguelbraga — Wed, 20 Jan 2016 10:51:16 GMT

Hey Santhosh N,

Check out these posts:

https://community.qlik.com/blogs/qlikviewdesignblog/2013/10/29/clarity-vs-speed

https://community.qlik.com/blogs/qlikviewdesignblog/2013/10/22/a-myth-about-countdistinct

Regards,

Re: Chart failed to load

santhosh_k_n — Wed, 20 Jan 2016 11:09:59 GMT

Thanks MB.

But this doesnt provide solution. Am using sum() function in my expressions and the memory and cal time are considerd from the document properties.

Regards,

Re: Chart failed to load

miguelbraga — Wed, 20 Jan 2016 11:11:32 GMT

Can you provide us a screenshot and/or sample(dummy) qvw of your problem?

Thanks,

Re: Chart failed to load

miguelbraga — Wed, 20 Jan 2016 11:20:28 GMT

See these posts:

https://community.qlik.com/thread/192984

https://community.qlik.com/thread/190877

https://community.qlik.com/thread/92504

Try organize better your data model. A star-schema model is typically faster than a snowflake or a single table. Try reducing the amount of expressions in each straight table using buttons where the user can see only the expression that they want.

Hope it helps...

Re: Chart failed to load

jonathandienst — Wed, 20 Jan 2016 11:21:19 GMT

Do the charts that are slow-loading contain expressions and dimensions that span multiple tables in your data model? This causes QV to perform an in memory join of the tables. If the association is poor, the in-memory requirements could be huge and the chart becomes very expensive to build.

Also Aggr() functions, calculated dimensions and sum(if()) type structures are slow and expensive to calculate.

If you need specific help on optimising the data model, you will need to provide a lot more information.

Re: Chart failed to load

santhosh_k_n — Wed, 20 Jan 2016 13:26:46 GMT

Hi Jonathan,

Yes the chart contains 4 dimensions and 9 expressions, and couple of expressions are of sum(if()) type.

I tried to replace the sum(if()) with section access conditions but the calculated time and the memory occupied remain same.

The datamodel is optimizes and the issue is only in 2 out of 9 charts am presenting.

Regards,

Re: Chart failed to load

Peter_Cammaert — Wed, 20 Jan 2016 13:40:21 GMT

Section Access? You mean Set Analysis?

That doesn't sound logical. Your performance problems point to charts being filled with a large number of data rows. In that case, the performance improvement that set analysis brings would be considerable. If no improvement can be measured, there is either something wrong with the other expressions (replace all IFs with set analysis) or there aren't that many rows to process. In which case there wouldn't be a performance problem in the first place.

Jonathan pointed out that a poor association could be the cause. A specific case of poor association is a butterfly connection where two tables connect large numbers of rows in each using few distinct values. Causes something that looks almost like a cartesian product (Gysbert used to manage those). Both calculation time and memory requirements may hit the ceiling.

Peter

Re: Chart failed to load

Wed, 20 Jan 2016 13:46:17 GMT

Try to avoid complex calculation if you are using any, you can minimize the chart because minimized chart will take less memory.

If you can upload your app or any sample app replicating your scenario then we would be able to give you more ideas.

Re: Chart failed to load

santhosh_k_n — Wed, 20 Jan 2016 13:50:10 GMT

Sorry peter.

ITs set analysis and i had typed incorrect.

I had replaced all the sum(if()) with set analysis but the issue is still open

Regards,

Re: Chart failed to load

NareshGuntur — Wed, 20 Jan 2016 13:52:24 GMT

Generally QlikView tries to calculate all the objects of the sheet(unminimized) at a time and so the cores get divided. So, most complex charts among the sheet objects are failing to load.

Can you try minimizing those two charts and then maximize them individually and check if they load?

Cheers,

Naresh

Re: Chart failed to load

santhosh_k_n — Wed, 20 Jan 2016 13:56:46 GMT

Hi Naresh,

I tried to load only one of the chart in a separate sheet but the result is same.