How to replace a null value ?

[#1]

Hey everyone,

When I load a table, there are some null values in a field. I use this field to perform a join. I would like to replace the null values by a string "Unknown" because otherwise I get some trouble with my join.

I have tried :

if( isnull(fieldA), 'Unknown', fieldA ) as FIELD_A,

but it doesn't do what I want.

Any idea ?

Thanks for your help

[Anonymous]

if  ( not  len(fieldA) > 0, 'Unknown', fieldA ) as FIELD_A,

[senpradip007]

Try like:

if(len(fieldA)=0, 'Unknown', fieldA) as Field_A

[MK_QSL]

If(IsNull(fieldA) or Len(Trim(Replace(fieldA,'-','')))=0, 'Unknown',fieldA) as fieldA