Background The discussion about the pros and cons of NULL in SQL has been raging for as long as SQL has been around. In this post I won't dare wading into this controversy. For those interested in such matters I point to the paper "Much ado about nothing" by C.J. Date. Here, instead I want to discuss the implications of NULL, given that it is part of DB2's SQL. What is NULL? NULL represents the absence of a value. Technically it is not a value in itself. However we often use the phrase...
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