Qlik Community

QlikView App Dev

Discussion Board for collaboration related to QlikView App Development.

Announcements
Support Case Portal has moved to Qlik Community! Read the FAQs to start exploring Support resources.
cancel
Showing results for 
Search instead for 
Did you mean: 
rupaliqlik
Creator
Creator

Synthetic Keys are Good or Bad?

@hi Guys ,Please tell me what are the disadvantages or advantages of synthetic keys ?

3 Replies
oknotsen
Master III
Master III

No advantages except that it makes an otherwise not allowed data model in Qlik possible.

Synthetic keys are the result of your data model having two (or more) tables with two (or more) field names in common. Qlik only allows a single field to be the relation between two tables, so it creates a helper table and a synthetic key to achieve this when your data model does not fit the rules.

The downside is that it is more resource heavy, can cause your calculations to go wrong and makes your data model harder to read, so we always advise to try and remove them.

In 99% of the cases removing a synthetic key is very easy:

- Rename fields that are not the same thing

- Remove fields that are double (as in "the same data in multiple tables")

- Use Qualify

May you live in interesting times!
swuehl
MVP
MVP

Have a look at a classic discussion thread

https://community.qlik.com/message/1065803?tstart=0#1065803

and Henric's response to that:

Synthetic Keys