How much does MySQL need to do?

Question

Am I writing an application and using MySQL to return the difference between two dates in MySQL, if MySQL does this, or should I let PHP handle it?

I also need the sum of all the results that I return, should I return them and add them on the php side, or is there a way to add all the results together on the MySQL server side?

Answer 1

It depends on the application in some ways, but in general I would push it to PHP, because usually you create a website for several simultaneous accesses; why invest in a database and possibly have a bottleneck?

Answer 2

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Answer 3

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, MySQL :

SELECT id, SUM(price) FROM items GROUP BY id WITH ROLLUP

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Answer 4

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