Skip to main content
Announcements
Do More with Qlik - Qlik Cloud Analytics Recap and Getting Started, June 19: REGISTER
cancel
Showing results for 
Search instead for 
Did you mean: 
Not applicable

difference between peek & previous , mapping & apply map , snow flake & star schema , QV10 & QV11

difference between peek & previous , mapping & apply map , snow flake & star schema , QV10 & QV11

9 Replies
kaushiknsolanki
Partner Ambassador/MVP
Partner Ambassador/MVP

Hi,

     Kindly go through the Help available with the QlikView Desktop.

     That content is the easiest to understand the different functions of qlikview.

Regards,

Kaushik Solanki

Please remember to hit the 'Like' button and for helpful answers and resolutions, click on the 'Accept As Solution' button. Cheers!
Not applicable
Author

hi please go through this for peek and previous

Not applicable
Author

hi go through this link for star and snow flake schema

Data Warehouse Schema Architecture - star schema

Not applicable
Author

hi go through this qvw file for mapping

SunilChauhan
Champion II
Champion II

peek is used to find any of the record from a table

like last and first record

previous will fetch only previous Record. see more in open qlikview and press F1.

previous(fieldName) and peek(fieldname) gives same result

mapping keyword hide the table from model

and applymap is used to merge a column on the basis of key field into other table based on mapping table

snow flake have secondary dimesions also

where as star  dimesion table are connected to fact table creating a star.

in star if you select any thing then sortest path will be apply .but in snow flake it migt be take more time to trverse as we have secondary dimesions.

star is good in respect to analysis and selections

snow flake is good for memory optimizations

hope this helps

Sunil Chauhan
its_anandrjs

Refer the below documents for the Peek and Previous and take reference from the reference manual

http://community.qlik.com/blogs/qlikviewdesignblog/2013/04/08/peek-vs-previous-when-to-use-each

Peek() vs Previous() – When to Use Each

ashfaq_haseeb
Champion III
Champion III

Hi,

Regarding Start Schema and Snowflake Schema,

Please find the document attached.

hope it help.

Regards

ASHFAQ

manojkulkarni
Partner - Specialist II
Partner - Specialist II

Snowflake Schema

Star Schema

Ease of maintenance / changeNo redundancy and hence more easy to maintain and changeHas redundant data and hence less easy to maintain/change
Ease of UseMore complex queries and hence less easy to understandLess complex queries and easy to understand
Query PerformanceMore foreign keys-and hence more query execution timeLess no. of foreign keys and hence lesser query execution time
Type of DatawarehouseGood to use for datawarehouse core to simplify complex relationships (many:many)Good for datamarts with simple relationships (1:1 or 1:many)
JoinsHigher number of JoinsFewer Joins
Dimension tableIt may have more than one dimension table for each dimensionContains only single dimension table for each dimension
When to useWhen dimension table is relatively big in size, snowflaking is better as it reduces space.When dimension table contains less number of rows, we can go for Star schema.
Normalization/ De-NormalizationDimension Tables are in Normalized form but Fact Table is still in De-Normalized formBoth Dimension and Fact Tables are in De-Normalized form
Data modelBottom up approachTop down approach
Not applicable
Author

Hi,

I have attached the example Qvw Of Apply map And Mapping,Peek() Function You will get brief explanation in Qlikview Help.