coalesce?

[raysefo]

Hi,

I m trying to use coalesce but i m getting this error below, btw i m using db2 8.2.
what i m doing is;
...
where eh.toblm = coalesce(NULL,eh.toblm)

SQL0206N "NULL " is not valid in the context where it is used.

Actually what i want to do is, get the result of this select statement either @id is NOT NULL or NULL! if @id is NULL then all results should be displayed!
...
where eh.toblm = coalesce(@id,eh.toblm)