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Databases

Posted by Daniel Alarcon
Daniel Alarcon
8,019 Points

Since operators were used on dates (i.e. <, >), I imagine other operators can be used as well, such as (+, -, * or /)

I imagine this can be done because computers internally assign numbers to dates... (?) And I can't imagine other cases other than addition or substraction to compare a given date, maybe division and finding out if a year is a leap year

2 Answers

Steven Parker
Steven Parker
231,261 Points
Steven Parker
Steven Parker
231,261 Points

Dates can be compared directly, but to perform calculations on them, you'll first need to convert them to julianday or make use of the modifiers available in the date() function.

There's a video about Calculating Dates in the Reporting with SQL course.

Daniel Alarcon
Daniel Alarcon
8,019 Points
Daniel Alarcon
Daniel Alarcon
8,019 Points

Thanks Steven. Good to know. I was aware that operations could be performed on dates. It's useful to learn about the julianday conversion. I knew other systems/software handled dates too and that operations were viable, but I wasn't exactly sure how MySQL did that. I already took the Reporting with SQL course, so maybe I missed references to julianday conversion but I do remember date modifiers were mentioned.