9 March 2023 Column references in Qlik Sense Share this message Every Friday at Bitmetric we’re posting a new Qlik certification practice question to our LinkedIn company page. Last Friday we asked the following Qlik Data Architect certification practice question about column references in Qlik Sense. We were actually quite surprised when we encountered this answer and given the fact that the answers are almost spread equally between A and D it seems you are too! The correct answer is A Column references in Qlik Sense The column() function in Qlik references a column in a straight table. Within the parentheses you can specify which column to target, Column(1) being the first column after all dimensions, since these are disregarded. As we can see in the chart above referencing a column does not imply referencing the actual values in the column, but rather the expression used in it. In the reference column the expression is calculated again. That’s why the column gives different results when using the random function. Calculation speed The use of the Column() syntax is mostly one based on quick debugging, doing on the fly validation or summing multiple columns. And in the latter case, does it speed up things? We have tested this on a dataset containing 5 million rows and a variable for margin: SET vMargin = 1 - (Sum(Revenue) / Sum(CostPrice)); With the help of the Qlik Sense Document Analyzer Pro we can see the effect of the calculations in the duration of the load of the following tables: We have ran the analyzer three times. One time with only the column containing the expression $(vMargin), The other time with $(vMargin) and Column(1). The final time with $(vMargin) in both colomns. QSDA Pro is a great tool to analyze sheets and find out metric about the performance and where to improve. In this case the SaaS app [TST] Column (containing the tables pictured above) is loaded and evaluated: Now if we press view, we can get an overview of all statistics of the app. We press the button ‘Sheets’ for the details on a sheet level: It is quite clear that the loading times are quite long. It takes almost eight seconds to load the table with only the variable. But it is more interesting to see what happens with the other two. Using the Column() function to reference the first column is actually the slowest. It takes three to four seconds longer to load the extra column. So be aware you want to calculate totals on a chart with many columns and measures. Using column will calculate all these measures again per column, accumulating to a heavy and slow loading chart. That’s it for this week. See you next Friday? Take your Qlik skills to the next level! If you enjoy Qlik, you’ll love the Masters Summit for Qlik. 3 days of Qlik deep dives, peer networking, ready to use resources and much more! See you there! Test your Qlik knowledge! Check out the Friday Qlik Test Prep archive for more Qlik questions and answers. Expressions Friday Qlik Test Prep Solution How can we help? Feel free to contact us if you have any comments or questions. Call us Mail us 21 September 2023 Qlik Sense Enterprise for Windows – Critical Security Fix #2 A new security issue in Qlik Sense Enterprise for Windows has been identified. This resolves an incomplete fix for the vulnerability that was reported earlier this month. Patches are available and it is recommended to update your Qlik Sense Enterprise for Windows environment at the earliest possibility. New Release Qlik Security 6 September 2023 Battle Ships & Big Data: join us for some fun! Unleash the Power of Data in the Ultimate Battle Ship Game! Join us at the Big Data Expo for a thrilling experience that blends strategy, competition, and analytics. Discover how data influences gameplay and be part of our research! Plus, dive into the world of data and analytics with the experts from Bitmetric. Don’t miss out! See you at booth 46! Bitmetric Event Qlik Team 29 August 2023 Qlik Sense Enterprise for Windows – Critical Security Fixes Two security issues in Qlik Sense Enterprise for Windows have been identified and patches made available. Details can be found in Security Bulletin Critical Security fixes for Qlik Sense Enterprise for Windows (CVE-2023-41266, CVE-2023-41265). New Release Qlik Security
21 September 2023 Qlik Sense Enterprise for Windows – Critical Security Fix #2 A new security issue in Qlik Sense Enterprise for Windows has been identified. This resolves an incomplete fix for the vulnerability that was reported earlier this month. Patches are available and it is recommended to update your Qlik Sense Enterprise for Windows environment at the earliest possibility. New Release Qlik Security
6 September 2023 Battle Ships & Big Data: join us for some fun! Unleash the Power of Data in the Ultimate Battle Ship Game! Join us at the Big Data Expo for a thrilling experience that blends strategy, competition, and analytics. Discover how data influences gameplay and be part of our research! Plus, dive into the world of data and analytics with the experts from Bitmetric. Don’t miss out! See you at booth 46! Bitmetric Event Qlik Team
29 August 2023 Qlik Sense Enterprise for Windows – Critical Security Fixes Two security issues in Qlik Sense Enterprise for Windows have been identified and patches made available. Details can be found in Security Bulletin Critical Security fixes for Qlik Sense Enterprise for Windows (CVE-2023-41266, CVE-2023-41265). New Release Qlik Security