Hi,

I've used IsNull many times and it works (mostly).

However I'm having difficulty with it when table data doesn't exist.

I have a main report and subreports which pass data back to the main report and it all works fine but sometimes I get an error in the main report stating various errors. I can see the problem is that there is no data at all. So I have deduced there is an issue with how to handle Null information on the subreports.

As an example below is a snippet of code.....

// Quantity on Hand
If IsNull ({inventory.qty_on_hand}) Then
    QoH := 0
Else
    QoH := {inventory.qty_on_hand};

For some reason this falls over when table data doesn't exist. Is there a way to force a zero in this situation?

No. However, I just read the help files on this and have a better understanding of this and have now changed them all (including the default).

However I still get an error. One of the subreports which is looking for the data has just one formula as shown below.

Shared StringVar sales_hist_cy;
StringVar hist;

If IsNull({invhist.qty_sale}) Then
    hist := "0;0;0;0;0;0;0;0;0;0;0;0;0"
Else
    hist := {invhist.qty_sale};

Local NumberVar hh := Len(hist);

sales_hist_cy := Left(hist,hh-2)

The intention is to find the data and remove the last two characters on the right because I only need 12 elements.

The formulas on the main report are showing an error that states the shared variable sales_hist_cy is equal to "" (nothing). The syntax for the variables is correct. I've checked that many times to be sure.

As mentioned above, the product has no history and thus there is no entry in the table that stores the data. This is not a common occurrence but happens enough to be a problem.



Edited by SteveDLC - 11 May 2016 at 7:04pm

Hi,

Looks like the 'Default Value for Nulls' along with another variable on the main report checking to see if it is indeed Null seems to work. I've tried to break it with know problem causers and so far, so good.

Thanks for your help.