In the summary of his column on DB2 NULLs in IDUG Solutions Journal Craig Mullins writes: "Nulls are clearly one of the most misunderstood features of DB2-of most of SQL database systems for that matter. Although nulls can be confusing, you cannot bury your head in the sand and ignore nulls if you choose to use DB2 as your DBMS. Understanding what nulls are, and how best to use them, can help you create usable DB2 databases and design useful and correct queries in your DB2 applications."