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agni_gold
Valued Contributor II

What are database used in qlikview

What are database used in qlikview and why and how ,

how to capture data in qvd and where to store this data,

what are the limitation of database used in qlikview,

and which type of data modeling supports

its urgent.

7 Replies
MVP
MVP

Re: What are database used in qlikview

Hi,

You can use any standard databases like SQL Server, Oracle, DB2, Informix, MySql, MS Access etc. You can connect to his databases by using ODBC or OLEDB connections.  (You can check help file for CONNECT statment).

You can fetch data from database by writing select queries and then store that table info into qvd by using STORE command in Qlikview. (You can check help file for STOREstatment).

Qlikview supports both Star and Snowflake schema, but in my view Star Schema is the best option, because it reduces the number of joins during runtime.

Hope this helps you.

Regards,

Jagan.

agni_gold
Valued Contributor II

Re: What are database used in qlikview

Hi Jagan

Thanks for the response.

But i am still confused which database i should use can you please provide me detailed knowledge about this.

And which type of data model should be best for use . And why and How can i use data model. please tell me limitation of that data model.

Which data modelling is best to use (Dimensional or Relational) .

Not applicable

Re: What are database used in qlikview

hi

Qlikview connect with different types of databases like

excel (for direct connect with excel)

ms access (use odbc/oledb and make dsn for connection)

oracle (use odbc/oledb and make dsn for connection)

mysql (use odbc/oledb and make dsn for connection)

sql server (use odbc/oledb and make dsn for connection)

sap (by the use of sap connecter).

syntax for capture data in qvd.

firstly in qlikview we store data in qvd, because in qvd up to90% data are compressed . so at the time of loading take few minute.

syntax-

store tablename into D:\tablename.qvd (qvd);


note-

qlikview work on ETL(extract transform loading).

so qlikview firstly extract the data from different sources.

then qlikview transform these data in own form.

then after transform use logic on it.

Not applicable

Re: What are database used in qlikview

Hi,

So many questions so let's take them 1 by 1

1. How to get data from qvd and store date into qvd

QVD means Qlikview DataFile.  To store data into qvd just

Store * from table into filename.qvd  will store the data from table into qvd file.

These data are loaded in Qlikview app before either from one or many files or database tables.

2. Database

QlikView can read data from any database (oracle, mysql, access....) using ODBC or OLE DB connection. (declare your database and use wizard).

As far as I know there is no limitation. At least, I never met it.

3. Data Modeling

QlikView uses a star (or snowflake) data model.

QV makes natural join on fields ahving the same name (Ex : Name from T1 and Name From T2 will be joined as a key)

You must avoid many fields in common in different tables and solve it as composite fields

I hope it helps enough for a start

best regards

Chris

rajeshvaswani77
Valued Contributor III

Re: What are database used in qlikview

Hi Agnivesh,

From QlikView you can read from any of teh databases as Jagan has mentioned. Once you do the reading you will store the data in to .QVD files. The QVD file is also called as an QlikView Database. The Data Modelling in QlikView sed is Dimensional Modelling. The Schema preferred is Star Schema, in some cases you would have a Snow Flake Schema. This would give you optimal performance since the way QlikView stores data for repetitions is in an optimal way. Hope my reply is helpful.

thanks,

Rajesh Vaswani

Employee
Employee

Re: What are database used in qlikview

QlikView does not need a internal database in order to work.

It loads all data into memory and when you need to persist you use qvd files (filesystem objects).

QlikView extracts data from almost everything.

agni_gold
Valued Contributor II

Re: What are database used in qlikview

Thanks for reply

What type of logic and methods  we can use on qvd file?

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