how to handle null values in qv

[#1]

Hi,

  please any one explain 'how to handle null values in qv'

Thanks

Reddy

[erichshiino]

Hi,

There are many ways to handle it.

You can test if a value is a null with the isnull( expression )

you can generate a null value with null()

You can use nullcount() as you use count() to count null values (script or in a chart)

You can use NullasValue to define the the null values in a field should be considerer as regular values for selections.

The syntax is:

NullAsValue A,B; // to apply this to fields A and B

You can go to help on QV and search for null to get more details

Hope this helps,

Erich

[siva_boggarapu]

Hello Narendra Reddy,

I hope that is good answer what he(Erich Shiino) posted. Better go thourgh the QlikView Reference manual. It will come automatically once you install QlikView software.

[#4]

You can find information in the document QlikView Reference Manual (cf 24.10)

[#5]

It does sound like

narrireddy is writing a test and hoping the wonderful community at QV can help him pass

[#6]

There are lots of Null values floating around in data and QlikView has some interesting ways to deal with it.

For example, we can turn on the NullAsValue option for a field that we are going to load:

Syntax : NullAsValue A, B;

Any values that were previously Null (and do not display in a list box) will now display as blank strings.

There is a small problem when you want to do any maths on a field that might have a Null value and that is that any number plus Null is Null. A great way to deal with this is, if I expect there might be Null values in a field, to use the Alt() function.

Alt accepts a list of values and will return the first of those values that has a valid number. So, instead of:

Load A+B as AB, ...

I can have:

Load Alt(A,0)+Alt(B,0) As AB, ...

Now, if either A or B have a Null value, it is treated as zero and my calculation can continue and give a good result.