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Prevent tables from automatic association?

Hi everyone,

I'm still new to qlik sense and I was wondering if there is any built-in function or way to prevent tables from joining (or keeping) automatically (haven't found anything in the documentation). I mean it's a great function but sometimes it feels a bit enoying to allways rename columns just to stop qlik from joining them with some other table.


Not sure if it does matter, but I have worked only with excel spread sheets yet.


Best regards


Update: I did mean preventing tables from association not from joining or keeping!

Nachricht geändert durch Mathias Gude

1 Solution

Accepted Solutions
Gysbert_Wassenaar

Tables never join automatically. Do you mean preventing association? That can only be done by renaming fields. That's because the only way to associate tables is to give the fields that should be used for the associated the same name. You can use the QUALIFY keyword to prefix all the fields with the table name. That will make the field names unique and will prevent any associations. It will result in data island tables which are likely to cause horribly bad performance and hard to predict results.


talk is cheap, supply exceeds demand

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3 Replies
Gysbert_Wassenaar

Tables never join automatically. Do you mean preventing association? That can only be done by renaming fields. That's because the only way to associate tables is to give the fields that should be used for the associated the same name. You can use the QUALIFY keyword to prefix all the fields with the table name. That will make the field names unique and will prevent any associations. It will result in data island tables which are likely to cause horribly bad performance and hard to predict results.


talk is cheap, supply exceeds demand
Not applicable
Author

Hi Gysbert,

thx for you reply. The QUALIFY function was exaclty what I was looking for and yes I did indeed mean association (I renamed this discussion). I dont want many separate tables and therefore data islands but I want to control the associated fields of the tables. I my case I got many data sources with identical field names and I didnt wanted to rename them all manually.

Thy for your help, I really appreciate it.

afrancisnrs
Contributor
Contributor

This also applies to the automatic union. Using the column name change works to stop.

//example - assume there are two large tables TableA and TableB with a common column called 'period'. Both need to be filtered in a data dependant way.

FilterTableA: load max(period) as period resident TableA;

FilterTableB: load max(period) as period resident TableA;

// After this FilterTableB does not exist, this is not an association, it is behaving like a union, could be a bug in the language? Renaming columns then is a round the house way to archive the filtering required.