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Search - "cartesian product"
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Not about favorite language but about why PHP is not my favorite language.
I recently launched a web shop built on Prestashop. I found that some product pages are so god damn slow, like taking 50 fuckin' seconds to load. So I started investigating and analyzing the problem. Turns out that for some products we have so many different combinations that it results in a cartesian product totalling about 75K of unique combinations.
Prestashop did a real bad job coding the product controller because for every combination they fetch additional data. So that results in 75K queries being executed for just 1 product detail page. Crazy, even more when you know that the query that loads all these combinations, before iterating through them, takes 7 fuckin' seconds to execute on my dev machine which is a very very fast high end machine.
That said I analyzed the query and now I broke the query down into 3 smaller queries that execute in a much faster 400 ms (in total!) fetching the exact same data.
So what does this have to do with PHP? As PHP is also OO why the fuck would you always put stuff in these god damn associative arrays, that in turn contain associative arrays that contain more arrays containing even more arrays of arrays.
Yes I could do the same in C# and other languages as well but I have never ever encountered that in other languages but always seem to find this in PHP. That's why I hate PHP. Not because of the language but all those fucking retarded assholes putting everything in arrays. Nothing OO about that.2 -
Saw a question on SO asking why foreach was slow with big data.
The code provided was 6 nested foreachs (basically a cartesian product between an array of arrays, and 4 other arrays).
Inside, a select query and an "update or create" operation.
"But why is foreach so slow?"4 -
So.. name one fucken case where your database is not a computer backed thing.
Just asking because.. why the fuck? I don't think your database server supports input of fucking math symbols? JUST USE HUMAN LANGUAGE, AS YOU HAVE TO DO ANYWAY!
It's stupid how everything needs to be expressed mathematically ffs. Not that it's hard to understand - it's just more complex than of a very simple wording.5