In my shapefile, I have calculated some indicators for each polygon. Now I want to create a new field having sum of these indicators.
I created new field and populated it with desired values using expression in QGIS. But, the resulting column have some blank rows despite not all of the indicators being
NULL. it is observed only for those rows, where any of the indicator is
NULL. I have used this expression
and here are all the values:
How to solve this?
"crabs" + "schrimps"instead of
crabs + schrimps
nullif()does the oposite: if
value2, then the function returns
Null, else it returns
value1. In this case, if
crabs==0then the function returns
Null, else it return the value of
crab... which remains