topic Primary Key Exception in Lookup in Qlik Compose

Primary Key Exception in Lookup

Ray0801 — Fri, 14 Mar 2025 20:49:07 GMT

Hi,

I have two tables orders and customers,

I am trying to add the orders table as the lookup for the Order_Id column in Customers

My condition is Cust_Id=Ord_Cust_ID

I am getting a Primary Key Violation Error while Running

Re: Primary Key Exception in Lookup

TimGarrod — Mon, 09 Nov 2020 15:56:54 GMT

The customer table Key (Natural or business key) is customer_id. By performing a lookup to orders - Compose will generate a left join - thereby creating multiple records with the same customer_id value. Which then triggers the PK validation check. (Multiple records for the NK).

Can you explain a little further what you are trying to do here?

Are you trying to get the last order_id for each customer or ?

If you are trying to relate orders to customer - then the relationship should be defined on the order table (with customer as the parent). This screenshot may show creating the relationship in the wrong direction ?

Re: Primary Key Exception in Lookup

nikhilraorane65 — Thu, 01 Apr 2021 05:50:23 GMT

Hi Ray,

You are getting this error as their is a one to many relation between Cust_Id and Ord_Cust_ID due to which cust_id which is the key in your table is getting repeated giving a primary key voilation detected.

As per my knowledge lookup here is doing a left join .

Regards,
Nikhil