Like we have If Not Exists in T-SQL, Is there any alternative in MDX ?

Hi All,I am a newbie in MDX. I am trying to execute MDX query through SSIS Execute SQL Task. I have set Single Row as a result set. Every thing is fine, But the problem arise when the query does not return any result.Because , this is the property of Execute SQL Task that it fails , If result set is SET and query does not return any value.This occurance is handle in T-SQL by used of If Not Exits/If Exists , Do we have something over here i.e. MDX ?If not then what might be the alternative for this.