Replace values from one column to another

[Tribhuwan]

Hello Everyone,

I am new to Qlik Sense and need your help.

I have 2 tables CSP and Segment and both tables have 5 common columns:

FUP_ID
FUP_NAME
GCN_ID
GCN_Name
GCN_ID_TYPE

CSP table has the latest and most updated FUP_ID and FUP_Name, where as Segment table has updated GCN_ID and GCN_Name

Now I want to join them in such a way that the GCN_ID and GCN_Name should be replaced with FUP_ID and FUP_Name where they are not matched and wherever FUP_ID column is not blank.

I have tried it getting the below output (which is wrong):

IVCOMPANYID	IVNAME	FUP_ID	FUP_NAME	GCN_ID	GCN_Name	GCN_ID_TYPE
1031752	Orchard Information Systems Limited	962419	MRI Software LLC	1031752	Orchard Information Systems Limited	IV ID
1038300	ZKW Zizala Lichtsysteme GmbH	816526	LG Corp	1038300	Zizala Lichtsysteme GmbH	IV ID
1039052	King's College London	15029	University Of London	61658933	Inspired Education Holdings Limited	IV ID
50509353	Candy Hoover Gmbh	4077389	Haier Group Corporation	1053829	Candy Hoover Group Srl	IV ID
62365458	Rip Curl	1226175	Rip Curl Group Pty Ltd	2521048	Kathmandu Holdings Ltd	IV ID
50220034	SLB 2020 Limited	50220034	SLB 2020 Limited	10897469	Greybull Capital LLP	IV ID
1100724	Lightstone Value Plus Real Estate Investment Trust Inc.	1100724	Lightstone Value Plus Real Estate Investment Trust Inc.	21235	The Lightstone Group LLC	IV ID
1152617	FFastFill Inc.	10870183	ION Investment Group Limited	1152617	FFastFill Inc.	IV ID
1379535	Hafslund USA, Inc.	61622666	Hafslund E-Co AS	861489	Hafslund ASA	IV ID

My desired output should look like the one given below (where FUP_ID and GCN_ID are same):

IVCOMPANYID	IVNAME	FUP_ID	FUP_NAME	GCN_ID	GCN_Name	GCN_ID_TYPE
1031752	Orchard Information Systems Limited	962419	MRI Software LLC	962419	MRI Software LLC	IV ID
1038300	ZKW Zizala Lichtsysteme GmbH	816526	LG Corp	816526	LG Corp	IV ID
1039052	King's College London	15029	University Of London	15029	University Of London	IV ID

Below is my script:

CSP:
LOAD
S.no.,
"Account Name",
"DiscoverOrg ID",
IVCOMPANYID,
GCN_ID,
GCN_NAME,
GCN_ID_TYPE
FROM [lib://Excel File Location (internal_tsingh1)/Qlik Test Data.xlsx]
(ooxml, embedded labels, table is Sheet2);

Segment:
Left Join(CSP)
LOAD
"FUP_ID",
"FUP_NAME",
if(GCN_ID<>FUP_ID or not isnull(FUP_ID),FUP_ID,GCN_ID) as GCN_ID,

"GCN_NAME",
"GCN_ID_TYPE",
"IVEMPLOYEES",
"IVINDUSTRY";
SQL SELECT "GCN_ID",
"GCN_NAME",
"GCN_ID_TYPE",
"FUP_ID",
"FUP_NAME",

"IVEMPLOYEES",
"IVINDUSTRY"
FROM "EDWC_CAMPAIGNS"."CVF_T_MKT_IV_COMPANYDETAILS";

Could anyone of you please guide me how can it be done and what I am doing wrong here.