Ask for Nothing and Get It
MOST MARKETING DATABASES are built using a relational database management system. That means somewhere, buried deep beneath all those sexy screens in whatever application you choose to employ, lurks a confusing and cantankerous beast known as Structured Query Language, more commonly known as SQL. Originally invented by IBM in the 1970s, SQL has become accepted as the industry-standard database access language. For marketers, it’s one of the few four-letter words in existence with only three letters.
My case in point here is the SQL term used to describe the absence of data: null. According to relational purists, if you don’t have data for a field in your database, then that field contains null. Null means nothing, empty, zippo, nada. It does not mean blank (a hard space) or zero. So if you think your checking account balance became null after Christmas, you’ll be relieved to know that this is not so. In fact, purists will argue that if a field is blank or zero it means you do know something about it, whereas if it’s null it means you don’t. Post-holiday spending, you’ll be happy to hear that zero only means you’re out of money. Less than zero means you’re in trouble. Null means you don’t even know if you have a checking account
