topic Replace Link keys in Qlkview in QlikView

Replace Link keys in Qlkview

ankitg4688 — Sun, 03 Sep 2017 19:27:55 GMT

Hi,

We can form a link table and a link key when there are multiple common columns across fact tables or dimensions. But, the link key slows down the performance of the dashboard if the data model is complex having many tables. Can we somehow replace this big link key and increase the performance of joins happening at backend and ultimately performance of charts in Dashboard?

Thanks for sharing the knowledge.

Br,

Ankit

Re: Replace Link keys in Qlkview

Anil_Babu_Samineni — Mon, 04 Sep 2017 02:27:47 GMT

I don't believe about performance because Link Key is very attraction and no issue in Perf. respect. Here, I would add my point from a & '|' & b as Composite_Key please change your script to Autonumber(a & '|' & b) as Linked_Key

Note - Chances are there to improve performance. If not, I would ask you to share structure of Data model and rows allocate to the Link Table?

Re: Replace Link keys in Qlkview

ankitg4688 — Tue, 05 Sep 2017 19:34:54 GMT

Hi Anil,

Thanks for your response. Actually, I am not aware about Autonumber function in case of Link keys. Could you please explain how does this work?

Thanks for sharing the knowledge.

Br,

Ankit

Re: Replace Link keys in Qlkview

Muthu — Wed, 06 Sep 2017 04:53:50 GMT

Autonumber function gives a unique integer number in the data model for the table.

autonumber ‒ QlikView

Re: Replace Link keys in Qlkview

jonathandienst — Wed, 06 Sep 2017 05:17:23 GMT

Link tables can perform poorly (slow recalculation times) if the cardinality of the link table is high. Autonumbering helps (and reduces the app size too), but I have learnt to be wary of link tables in large data sets.

However, you should have no problems with models of the order of 100k - 1M rows.

Re: Replace Link keys in Qlkview

ankitg4688 — Sat, 09 Sep 2017 07:14:45 GMT

Hi Jonathan,

My data model has 200 Million+ rows. 4 fact tables. 2 Common columns which are combined to form Link Key. And I am not using Autonumber function. Is it good to use Autonumber of Autonumberhash128? Will it increase the performance?

Thanks for sharing the knowledge.

Br,

Ankit

Re: Replace Link keys in Qlkview

effinty2112 — Sat, 09 Sep 2017 11:04:28 GMT

Hi Ankit,

Autonumber will be a far better choice than Autonumberhash128. An Autonumber field will take up much less memory and associating tables with integer keys gives much better performance than associating with text keys.

Regards

Andrew

Re: Replace Link keys in Qlkview

ankitg4688 — Wed, 13 Sep 2017 18:52:30 GMT

Hi Andrew,

Thanks for your response. I will try to implement as suggested.

Thanks for sharing the knowledge.

Br,

Ankit