Relational Database Index Design and the Optimizers (Wiley, July 2005) is an excellent book on how indexes work in general in a relational database. The authors focused on principles and not any particular database vendor. The book focuses on two things; first, the database optimizer of the relational system that has to decide to decide [...]
OVERLAPS predicate is a useful feature, which is not available in most SQL implementations that can help to determine whether the two periods overlap each other. If two periods overlap then the predicate evaluates to TRUE otherwise FALSE. Let us create a test table with three rows – one with overlapping dates, second with non-overlapping [...]
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