Cognos has been developed for many years and it is now. . . . . But what you have learned can't be buried, and I will give it to everyone today. I also hope that everyone will comment like, thank you.
How to optimize the long query time of reports with large data volume?
Source of ideas ibm official website: https://www.ibm.com/support/knowledgecenter/SSEP7J_11.1.0/com.ibm.swg.ba.cognos.ug_cra.doc/t_localfileoutputlocation.html
The first step : The data can be as persistent as possible, and the star model of the fact table associated dimension table is the most taboo in query processing when the amount of data is large.
Step 2 : Optimize SQL, optimize data storage without data skew.
Be sure to copy the sql automatically generated by Cognos. Although the format is messy and there may be more, it is still necessary. You can adjust some configurations of the sql generated by Cognos to optimize. Copy the sql, check the places that can be optimized.
The data tilt depends on the deployment of each database, whether it is multi-node load balancing, which affects SQL concurrency.
The third step : report SQL parallel processing, for the display of large data volume reports (for example, millions of data a day, nearly 100 display fields, a large number of window function processing and summary, 1 minute and 30 seconds before processing), split SQL Minutes, processing plan query fields, summary fields, performance can improve the time to query only the summary field sql. How does SQL split?
Dangdang Dangdang please see the following:
Prerequisite: Steps 1 and 2 have been processed, and the original report is still available and correct. The query subject is: query 1.
Click the report development page, click query in the query explorer to enter the query window, drag in a query subject, named: query 2, according to the summary field in query 1, drag the same summary field in query 2 (which may Need to use some functions). Then on the report design page, there is an unlock button in the report menu bar. Unlock it first, then delete the fields in the summary item, drag the single item to fill, and then insert the field in Query 2 into the single item, and it’s ok.
I have uninstalled Cognos, there is no picture, please be considerate, and you can leave a message if you have any questions.
Many people have also asked questions about Cognos, as follows:
How do multiple rows in the crosstab corner deal with data centering? Compatibility of different browsers causes not centering, and data export is not centered?
What is the method for exporting large data volume of Cognos report?
What is the problem with dynamic cube and power cube?
How to realize the business development report, and how to share the report after the development is completed, how to dynamically view it in the web menu? Did you hear the business development report correctly? Absolutely.
Cognos integrates hive and hive on spark runs batches. What is the purpose of integration? Isn't hive slow? Isn't spark on hive good?
. . . . . .
Stay tuned, stay tuned!
Author: Small also
learn, every day