Question

I am try to convert a decimal field null values(“0.0”) into empty string (“”) using nullif() method. But the conversion causing an error. I tried the same method for another int field, and it worked fine.

How can I convert decimal null values into empty strings in a sql queries?

Answer 1

1. SQL uses single quotes for 'values', double quotes for "column labels"
2. '0.0' is a string (for varchar columns), 0.0 and 0 are numbers (for int / dec columns)
3. neither '0.0' nor 0.0 are nulls
4. nullif() returns null for the right condition, not an empty string

so you probably want something like this:

case when mydecimal = 0 then '' else cast(mydecimal as varchar(10)) end

or:

nullif(mydecimal, 0)