Handling multiple dates within a table and from multiple tables

[achakilam1022]

Hi all,

 I was wondering which approach out of Canonical date, Date Island and Link Table would result in faster reload of data and charts for our data.  I have attached an image of how our data looks like. I appreciate any inputs on this.

Or could you please point me to an article that compares the pros and cons of these approaches? 

Thanks!

[dplr-rn]

for large data sets canonical would gie you best performance

check this blog series

https://optimalbi.com/crafting-qlik-sense-calendars-part-4-of-4-canonical-dates/

[achakilam1022]

We do have a very large data set and we are currently implementing a link table style solution like in the article. I was just wondering if there is a more optimized solution

[dplr-rn]

link table should work but canonical gives best performance as far as i know.

mark as answered if no more questions

[robert99]

Hi

Example.  I had many dates in 4 joined (keep) tables. Three I used canonical dates for and table 4 a date Island approach.

I removed the date island approach. It actually worked well but 

- It can't be used with a dimension. 

- It's different. And I forgot after a time what I had done when asked to adjust the App (this was starting out)

So I tried a Canonical Date for this table 4 (I was using it for the other tables) but it got confusing as there wasn't a clear finer grain table (table 3 vs table 4). So table 2 was missing calls from table 1. Likewise table 3 from table 2. This was overcome by making table 3 the finer grain table and adding the missing call numbers to table 2 and 3. But table 4 was missing calls from table 3 and table 3 likewise from table 4.

So I simple concatenated table 4 to table 3

My view is either use canonical  dates alone or canonical dates after concatenating tables.