Difference between Synthetic Tables and Circular loops give me an example

[jonesbrown]

Hi All

I am new to Qlikview 

Difference between Synthetic Tables and Circular loops give me an example

plz help.

[vikasmahajan]

Hi ,

Synthetic keys. When two or more data tables have two or more fields in common, this suggests a composite key relationship. Qlik Sense handles this by creating synthetic keys automatically. These keys are anonymous fields that represent all occurring combinations of the composite key.

Common Fields between 2 or more tables it is combination of same columns.

Circular Loops :  Qlikview & QlikSense works on associative technology , for this we need data path in data model  1 : 1

Defination:

Circular loop means you have alternative paths between two tables, so you need at least three tables in your data model to run into this. QV can't live with circular loops, it will break the loop by loosely couple one of the tables automatically.

Hope this clear's you concept.

Vikas

[martinpohl]

Synthetic Keys:

There are tables which are linked by more than one field.

Synthetic keys are allowed but unwanted, if possible don't use them.

For example if you have to link your datas within two field (OrderNo and OrderYear identify one clearly relationship between two tables). 

For that create in both tables on field (OderNo & Year as OrderNoYear) and in one table the single fields for selection.

Circular loops:

Your tables are linked between field so that there is a loop.

Example:

Table 1:

OrderNo, CustomerNo, CustomerName, Plant

Table 2:

CustomerNo, Plant

Table 3:

CustomerNo, CustomerName.

So there is a relation between Tab1 and 2, Tab2 and 3 and Tab 1 and 3.

For example the Customer Name is stored in table 1 and the moment of create the order, in table 3 it is the actual value.

This happend in many ERP systems.

So what do you want: 

historical name, actual name or both?

1 and 2 don't load the other field, in case that you need both rename the field (Name_actual and Name_order)

Hope this helps.

Regards