topic Re: data modeling in QlikView

data modeling

arulsettu — Wed, 25 Feb 2015 05:51:55 GMT

Hi,

i am having around 10 transactional(fact) table in my DB. and many other master(dimensional) table. to form schema what is the best way either can i concatenate all transaction tables or any other way?

please suggest some advice

thanks

Re: data modeling

Wed, 25 Feb 2015 05:57:34 GMT

Hi,

If all fact tables are having particular KEY field which is common in between all fact then link Key will be better approach may be efficient way to do data modelling..ELSE concatenate all fact in one ..

thanks

Re: data modeling

arulsettu — Wed, 25 Feb 2015 06:15:11 GMT

it will form snowflake schema. i know if i concatenate in to one it will give star schema. star schema will give better result? in optimization it is good?

Re: data modeling

arulsettu — Wed, 25 Feb 2015 06:23:24 GMT

need advice on this

Re: data modeling

Wed, 25 Feb 2015 06:29:36 GMT

Hi,

PFA,

Best Practices for Data Modelling

Hope it will help you..

Re: data modeling

Siva_Sankar — Wed, 25 Feb 2015 06:32:26 GMT

Hi Arul,

You need to consider the data quality, granularity and performance. Sometimes the star schema is good sometimes snow flake schema is good in performance. Check out best practices in data modelling to get good performance.

Re: data modeling

mukesh24 — Wed, 25 Feb 2015 06:52:20 GMT

Hi,

If u concatenate all 10 fact into 1 & build star schema but it will not give better performance. Because you simply adding number of record count into single table. Concatenate into single fact is good for small data size. If data size huge u need to think before simply concate all table.

Regards,

Mukesh Chaudhari

Re: data modeling

sujeetsingh — Wed, 25 Feb 2015 06:55:21 GMT

Follow this document

Best Practices for Data Modelling

Re: data modeling

arulsettu — Wed, 25 Feb 2015 07:00:58 GMT

Hi all thanks for replying my database is little huge. thats why i am asking if i concatenate i will better perfomance or is there any alternate suggestions

Re: data modeling

mukesh24 — Wed, 25 Feb 2015 07:02:39 GMT

If u r database huge i will suggest avoid concatenate, go for snowflake schema approach.

Re: data modeling

vinay_hg — Wed, 25 Feb 2015 07:22:00 GMT

yes.. if star schema is possible go ahead with that.

Re: data modeling

avinashelite — Wed, 25 Feb 2015 07:26:59 GMT

Hi Arul,

*If your having same columns in all the tables then concatenation will be good.

*If you don't have common columns then don't go with the concatenation, go with join .

Re: data modeling

mukesh24 — Wed, 25 Feb 2015 07:27:23 GMT

Hi ,

If u go for stars schema then u face performance issue.(Depend on u r datasize)

Regards,

Mukesh Chaudhari

Re: data modeling

arulsettu — Wed, 25 Feb 2015 07:33:04 GMT

Hi Avinash,

each table having common relation fileds

Re: data modeling

Wed, 25 Feb 2015 07:45:51 GMT

Hi Arul,

* If your Fact Tables having Same Field Names and data then you go for Concatenation, it is better..

* If You are not Having Same data then you go for Link Table and performance wise better even though it is not Start Schema ...

Re: data modeling

avinashelite — Wed, 25 Feb 2015 07:53:49 GMT

Hi Arul,

Then you can concatenate those 10 transaction tables by renaming the fields and using other tables build the data models. This will work fine

Re: data modeling

arulsettu — Wed, 25 Feb 2015 07:56:28 GMT

Hi Avinash,

the database size is little bit huge so it wont be a problem

Re: data modeling

avinashelite — Wed, 25 Feb 2015 08:07:16 GMT

no, if the 10 tables have same number of columns and same columns then it will be no issues