topic Re: Regarding Star schema to a single table in QlikView

Regarding Star schema to a single table

Wed, 25 Nov 2020 16:16:04 GMT

Hello Friends,

I am new to QlikView, can we convert star schema to one table in QlikView, if so why and if not even why?

please let me know.

Thank you in advance.

Jeevi

Re: Regarding Star schema to a single table

devarasu07 — Thu, 16 Mar 2017 02:00:56 GMT

Hi Jeevi,

It's depends upon your Business requirement and volume of your data. I would suggest to go with Star Schema model always because Star schema will usually result in the best performance for Qlikview applications.

Star Schema Emphasizes deep dive to check for different combinations by facilitating quick analytics in terms of query performance.

The reason why i don't go for Flat table can be a real nightmare to query against huge volumes of data.

In simpler words, Star Schema is as comfortable as having a Kitchen,DiningRoom,Bedroom,DrawingRoom,Bathroom etc in house rather having a single room for everything. Data FETCH becomes easier in Star Schema.

Hope this help you

Regards,

Deva

Re: Regarding Star schema to a single table

Siva_Sankar — Thu, 16 Mar 2017 02:09:52 GMT

Re: Single Table Data Model to Star schema

Re: Regarding Star schema to a single table

Thu, 16 Mar 2017 02:38:02 GMT

Thank you so much guys, I appreciate your time!

Jeevi

Re: Regarding Star schema to a single table

Siva_Sankar — Thu, 16 Mar 2017 02:47:08 GMT

Re: Regarding Star schema to a single table

Thu, 16 Mar 2017 03:07:59 GMT

Thank you!

Re: Regarding Star schema to a single table

ahaahaaha — Thu, 16 Mar 2017 07:30:00 GMT

Hi Jeevi,

Normalization of the structure of tables, ie. transition from one table to several related tables, is used to avoid duplication of data. This reduces the amount of memory used in the computer's memory. Accordingly, merging the data of several tables into one results in an increase in occupied memory due to the appearance of duplicate data.

There are no strict rules for organizing the structure of data tables, there are best practices and recommendations. With small amounts of data it does not really matter which of the two options to use.

Regards,

Andrey

Re: Regarding Star schema to a single table

oknotsen — Thu, 16 Mar 2017 09:58:17 GMT

If your question is now answered, please flag the Correct Answer (via the big "Correct Answer" button near every post).

If not, please make clear what part of this topic you still need help with .

Re: Regarding Star schema to a single table

Thu, 16 Mar 2017 12:52:53 GMT

Thank you Andrey!

Re: Regarding Star schema to a single table

imsushantjain — Tue, 02 Jul 2019 06:45:12 GMT

Can anybody explain why Single Table is bad for RAM Consumption and Script Run Time?

Re: Regarding Star schema to a single table

MEJ — Tue, 02 Jul 2019 09:10:38 GMT

What is considered small amounts of data? Is it based on the size of the QV application, or what the database structure looks like (the number of joining tables)?

I normally always try to create a single table in my applications, as I feel I understand the structure, and it is easier to create QVD files based on this, with the same structure, or to export the whole database to Excel.

Most of my applications are less than 100 MB in qvw format. Probably a small application compared to some (a few million records with 50 to 100 fields/dimensions). In some applications I have close to 1 GB. I might have a go at creating a star scheme instead, to see if they perform better.