Blanking a null

I have a SQL query returning the value of null.

Diagnosis4 = result1.getString('Diagnosis4');

I then have code to check if the value is "null"

if (Diagnosis4 == "null") {Diagnosis4 = " ";}

When I log an info statement for the value I get:

logger.info('Diagnosis4 : ' + Diagnosis4);

Diagnosis4 : null

I'm sure this is a simple noob fix but I for the life of me can't seem to get the Diagnosis4 to blank out if the value is 'null'.



You all rock BTW.

Blanking a null