topic Using From_Field in QlikView

Using From_Field

Mon, 23 Nov 2009 15:36:38 GMT

Morning,

Can anyone give me an example script of using 'From_Field' in loading fields. It will be great if the example load different fields from different tables. (e.g. a from table a, b from table b)

Regards,

Ivan

Using From_Field

prieper — Mon, 23 Nov 2009 16:33:12 GMT

Do you mean a JOIN in SQL? Or just load in QlikView and let QV combine them?

Peter

Using From_Field

Mon, 23 Nov 2009 16:53:46 GMT

Hi Peter,

Sorry for the confusion. What I mean here is: I have data(Weight or number) in table A under field 'Weight'. In table A, I also hasve key field 'ID'. 'ID' actually contains infomation on date(Year and month), data type etc. Date in Table B link to table A by 'ID' Data type in table C link to tabke B through a different key field. However, if choose the data in table A, the corresponding information from date and data type will be found.

What I am trying to do now is to do the aggr sum in script according to Date and Data type. I don't do it in front end because it costs too much resources when I do further calculation based on it. I tried sth like:

Load

Date,

Data_Type,

sum(Weight) as sub_total weight

from_field (here is the problem, fields are from different tables)

group by Date, Data_Type;

It is not working. Any suggestion.

Many thanks,

Ivan

Using From_Field

prieper — Mon, 23 Nov 2009 17:55:28 GMT

In the script this does not work. You will have to combine the tables into one (temporary) table, in which you will do the calculation. Results then might be linked back to one of the other tables (using ID or the like).
Within the application (Frontend) you can calculate across several tables - have you tried to do so? Usually with simple formulas the performance is not that bad.

HTH
Peter

Using From_Field

Mon, 23 Nov 2009 18:03:46 GMT

Thanks for the advices. The front-end calculation using formula is not that bad. But it become unacceptable slow when I apply other formula build on it.

It is a bit tricky to build a bigger table here ...but I will try.

Once again, thanks for your help!!

Ivan