A bit of theory of databases: The Halloween problem and the Table Spool
Hi Guys, Welcome to this second post of the year. Today we will talk a little bit of theory, we will talk a little bit of database theory in general and therefore not specifically of our SQL Server. Enjoy yourselves! The Halloween problem I don't know about you but " Halloween problem " makes me think of one of those old fairy tales that always hide a wise warning, one of those fairy tales lost in a past time which in our case is however the period in which relational databases were born and started to develop ... but let me tell you the whole story! This story begins around the mid-1970s. Ted Codd, a researcher working at IBM, had conceived relational databases a few years earlier. Also in those years both the idea of data normalization (who does not remember the third normal form learned at university?) And the ACID properties of transactions (we talked about it here) were born. It was the golden age of databases but at the same time pioneering! But let's go ...