Question

I’m trying to make up my mind between allowing one of my functions accept either an array of arrays or just an a standard array.

The array with arrays will allow me to verify each array key, but it is not necessary if I am able to see an improved performance from using a standard array.

Is there any performance difference between the two (performance wise)?

e.g.

arrays of arrays

$arr2 = array(
   array('isbn' => '1846031249'),
   array('isbn' => '0340912081'),
   array('isbn' => '0435446576'),
   array('isbn' => '1741845467'),
   array('isbn' => '0750924721'),
   array('isbn' => '1843286432'),
   array('isbn' => '011331079X'),
   array('isbn' => '9063325819')
);

normal array

$arr2 = array(
   '1846031249',
   '0340912081',
   '0435446576',
   '1741845467',
   '0750924721',
   '1843286432',
   '011331079X',
   '9063325819'
);

Answer 1

Don’t do an array of arrays! You are needlessly increasing the amount of information you need to store in memory/process through. And in your case, when each value is simply an ISBN, keep track of the array so that you remember what’s in it and scrap the repetitive labelling.