ISNULL Function

Hi Guys,

I am working on GL table, apparently I got NUll values in some columns. Columns data type are currency and I want to replace all the "NULLS" with 0. I am using derived column transformation and I ahve tried both the expression below but they are not working. Am'I missing something here.

ISNULL(ColumnName) == True ? "0" : ColumName

ISNULL (ColumnName) ? "0" : ColumName

Both the expressions are not working, this is right approach using derived columns or any other approach need to follow.

Thanks,

D