topic Re: Performance Issue with Left Join in QlikView

Performance Issue with Left Join

amit_saini — Mon, 25 Sep 2017 14:47:12 GMT

Hi Folks,

I'm having 45 tables in SQL named as Tab1,Tab2.....Tab45 ,which I have stored as QVD's.Each table is having column as below:

Like Tab1 is having 928 Columns , Tab2 =776 and so on. In all the tables I'm having ID as key to connect all 45 tables.

To connect the data , I have used left join like below, but performance is too slow.

Fact:

Load ID,

XYZ

---

From

Tab1

Left Join (Fact)

Load ID,

ABC.

From

Tab2

Left Join (Fact)

Load ID,

PQR

From

Tab3

Left Join (Fact)

Load ID,

HGT

From

Tab45

Row size is fine ,but I'm having so many Fields and all of them are important.

Can anyone suggest other ways of handling such data???

Thanks,

Amit

Re: Performance Issue with Left Join

vvira1316 — Mon, 25 Sep 2017 15:15:56 GMT

Hi Amit,

Just a thought. I'm not sure if you have explored and will help to join them on database side instead of QlikView side? Maybe joining several tables at a time, may be using resident tables.

BR,

Vijay

Re: Performance Issue with Left Join

amit_saini — Mon, 25 Sep 2017 15:24:54 GMT

Well the database is SQL , as there is limitation within SQL that user can't create more than 760 columns and this is the mail reason why the business has divided the data in 45 tables.

Thanks,