What is the significance of ' ' in the sql load command?

[#1]

I'm new to scripting sql in qlikview so this is probably a no brainer.

What is the significance of ' ' in the sql load command? How does it work and what's the purpose? See example code.

Thanks in advance

QTY_Table_TMP:
load
FRITNO as "Item",
FRCYP1 as "Month",
FRCUCL as "Customer_Grp",
ForecastQTY as Forecast_QTY,
' ' as "Open_po",
' ' as "Open_po_acc",
' ' as "PO_In_Transit",
' ' as "Open_orders",
' ' as "In_proces_co",
' ' as "Cancel_Date_Year",
' ' as "Cancel_Date_Month",
' ' as "Open_orders_acc",
' ' as "MO_Qty_TO_Acc",
' ' as "MO_Qty_TO",
' ' as "MO_Qty_From",
' ' as "MO_Qty_From_Acc";

sql select fritno, frcyp1, frcucl, sum(frorqt) as "ForecastQTY"
from xxxx.Forecast

[disqr_rm]

It means null value = nothing.

[#3]

So what's the purpose of using it?

How or why would you import a null value from a table and set it as a variable?

Can you give me some examples?

Thanks again

[johnw]

Doesn't make any sense to me either. Why create fields that have nothing but null values? But that's what it looks like is being done.

Hmmm, might be someone that doesn't know the CONCATENATE command. QlikView will automatically concatenate tables that have all the same field names. Perhaps this is someone's way of forcing this table to be concatenated with another table that DOES have those fields? Easier and I'd say better to just force it by telling it to concatenate.

To give you an example, maybe they're doing this:

[Table]:
LOAD A, B, '' AS C, '' AS D, '' AS E, '' AS F, '' AS G
FROM some source;
LOAD A, B, C, D, E, F, G
FROM some other source;

If so, while it gives the same results, it would probably be better to do this:

[Table]:
LOAD A, B
FROM some source;
CONCATENATE (

)
LOAD A, B, C, D, E, F, G
FROM some other source;