topic Re: How to create data model with cardanality in QlikView

How to create data model with cardanality

vipingarg23 — Tue, 03 Oct 2017 10:37:27 GMT

Hi Team,

I have three tables A,B,C , joining with each other (With Cardinality) as an attachment.

Can anyone please guide how should I proceed with data model creation means how to should I join these tables?

Re: How to create data model with cardanality

petter — Tue, 03 Oct 2017 11:06:22 GMT

In QlikView you can't restrict the cardinality but you can certainly create a physical model in QlikView according to this ER-model you have shown.

You create three tables just as in your diagram - A, B and C.

Table A should have a common field with table B and the same goes with B and C.

For instance:

A could have a field called A_B and the table B should also have a field named A_B. They should both contain values that would create a match.

C could have a field aclled A_C and the table C should then have a field named A_C too. And the same logic applies here - that they should both have values that would create matches.

This is similar to what you would do in a SQL database. The only difference here is that the matching fields have to match both on field names and (at least some) field values. In a SQL database you would define primary keys and foreign keys which is not necessary or possible in QlikView. Furthermore in a SQL database you would have to do "manual" joins which is not necessary in QlikView since that is done automatically via the Associative Model of QlikView.

Re: How to create data model with cardanality

petter — Tue, 03 Oct 2017 11:09:49 GMT

To be clear - the cardinality would be defined by actual field values and not by a declarative statement. So if you need that check you would have to do that with some code in your load script to test whether you do have the right cardinality and if not then issue a warning or an error message or throw some sort of exception.

Re: How to create data model with cardanality

vipingarg23 — Wed, 04 Oct 2017 13:09:42 GMT

Thanks Petter for your clarification.

Re: How to create data model with cardanality

Anonymous — Thu, 11 Oct 2018 11:45:17 GMT

Dear petter-s, I hope you are fine and in a good health. I have a question regarding this one. I have two fact tables and two conformed dimension, like the attached image.

Qlik Sense data loader gives me error that I've a circular relationships but according to my cardinality I don't have circular relationship!

I think if we have a way to set the cardinality explicitly, we will have no problem, do you agree with me?

BTW, I solved this issue by "concatenating" FCT1 & FCT