Preceding Load with calculated field

[kerkying]

Hi,

I am trying to load a calculated field with reference to a field loaded in a previous preceding load.

LOAD

FieldValue('Physical Column Name',1) AS TEST

FROM C:\Users\qvdTest.qvd (qvd);

REFERENCE:

LOAD [Physical Table Name],

     [Physical Column Name]

FROM

(txt, utf8, embedded labels, delimiter is '\t', msq);

I know that there is something wrong with the script but I don't wish to use something like LET vVariable1 = FieldValue('Physical Column Name',1) and load the variable as I potentially will have to create a lot of variables.

Any advice would be greatly appreciated thanks!

[kerkying]

Okay the entire solution is:

We have a schema that stores 2 fields, Physical Tables and Physical Columns. The data contained in all the tables is too large (5000 tables x ~2M rows of data) to be loaded in 1 QVW.

We have a requirement to allow users to do adhoc selection of any column to load it as a table view. It is sort of like choosing, for example, 8 columns from 3 tables out of a possible 10,000+ columns.

Because of this we had 2 list boxes to list out the Physical Tables and the Physical Columns. Users will make their selection and when they are done, click a button to export it into a .qvo config file.

What we see so far is to:

1. User makes selection

2. Export selection to .qvo file

3. Load the selection as new fields

4. Use the values from the new fields to load the actual data from the source QVD.

//Load the values from the fields to extract the actual data from the QVD.

REFERENCE:

LOAD

FieldValue('Physical Column Name',1) AS TEST

;

//Load the user selected fields

LOAD

[Physical Table Name],

[Physical Column Name]

FROM

(txt, utf8, embedded labels, delimiter is '\t', msq);

Right now what is failing is part 4. where the script does not recognize the formula / execute the formula while running the load.