topic Re: Join VS Link table in QlikView

Join VS Link table

debabrata_sahoo — Wed, 25 Nov 2020 16:16:04 GMT

Which is good in performance wise between join and link table. In my case I join 4 table with multiple join condition but having some performance issue. Please suggest me i will go for link table or not. if i will go for link table then need to create 3 linktable.

Example: let assume I have 4 table A,B,C,D.

A and B having some matching field

B and C having some matching field

C and D Having some matching field

There are no matching field between A and C , A and D, B and D

Re: Join VS Link table

tresB — Fri, 17 Aug 2018 09:35:08 GMT

Have a look here: Concatenate vs Link Table

Concatenate might be a better choice based on how many fields are in common between tables.

Re: Join VS Link table

ChennaiahNallani — Fri, 17 Aug 2018 09:39:57 GMT

if data is more create a view in Database and use it

Re: Join VS Link table

pooja_prabhu_n — Fri, 17 Aug 2018 09:43:10 GMT

Hi,

refer this link

https://qlikcentral.com/2016/11/24/should-i-link-or-concatenate/

Re: Join VS Link table

manoj217 — Fri, 17 Aug 2018 12:53:47 GMT

use join and link table.

for your condition you need to use 3 joins or 3 link tables instead of that use both then it will increase performance else use keep join

Re: Join VS Link table

manoj217 — Fri, 17 Aug 2018 12:54:14 GMT

instead of using join use keep join it will increase performance

Re: Join VS Link table

debabrata_sahoo — Tue, 21 Aug 2018 06:12:48 GMT

OK but I need outer join between these table . I used join but some performance issue happens in production.

So need to work on performance tune. So Please suggest on it.

Re: Join VS Link table

manoj217 — Tue, 21 Aug 2018 06:32:43 GMT

if you have data join will impact on performance instead of that use keep join it will not impact on performance but this function will show these two tables separately

Re: Join VS Link table

manoj217 — Tue, 21 Aug 2018 06:33:28 GMT

if you have huge data in your tables join will impact on performance instead of that use keep join it will not impact on performance but this function will show these two tables separately

Re: Join VS Link table

debabrata_sahoo — Wed, 22 Aug 2018 12:27:30 GMT

Thanks for reply. In my case 6-7 column are matched and in join condition I need to mention all these column. after using keep I will face synthetic key. I can use join else link table. My question is which is faster between join and link table. We have huge data in production. But i don't have access to production so not able to check.