topic Synthetic keys in QlikView

Synthetic keys

ferha_jafri — Thu, 08 Jun 2017 04:39:28 GMT

Hello Everyone,

I want to know that whether synthetic keys degrade front end performance or not , I know if they are present at the back end they will tale more loading time , but I am not sure whether they will degrade front as well.

Thanks in advance

Ferha Sharma

Re: Synthetic keys

prma7799 — Thu, 08 Jun 2017 04:42:53 GMT

Please check this

Synthetic Keys

Should We Stop Worrying and Love the Synthetic Key?

Re: Synthetic keys

Anil_Babu_Samineni — Thu, 08 Jun 2017 04:44:45 GMT

How you are seeing synthetic keys in Front-End. Because, Synthetic keys happened only in Back end i assume. So, synthetic keys are not good the reason is data model looks like references. So, It may kills the model as neat and clean.

More information please read https://www.analyticsvidhya.com/blog/2014/12/remove-synthetic-key-concatenation-link-table-qlikview/

Re: Synthetic keys

jonathandienst — Thu, 08 Jun 2017 06:02:38 GMT

A synthetic key is simply a compound key made up of two or more columns associating one or more tables. If this is what your data model requires, then leave them in. They will perform no better and no worse than a compound key built in your load script.

Having said that, the issue with synthetic keys is that they often arise in a poorly designed data models or after an error such as forgetting to drop a temporary table. This can result in a whole cohort of associated or partially associated synthetic keys which will degrade performance and possibly mangle the results of your metrics, as well as leading to partially decoupled tables because of logical loops.