Single quoted vs double quoted string
by Rekha[ Edit ] 2009-11-13 15:04:31
Use single quoted strings unless you need to interpolate variables into your string. This saves PHP the time to scan the string for contained variables and saves about 50% execution time.
<?php
function getmicrotime($t) {
list($usec, $sec) = explode(" ",$t);
return ((float)$usec + (float)$sec);
}
$start = microtime();
$a = array();
for($i=0;$i<100;$i++) {
array_push($a, "Aaron rules!");
}
$end = microtime();
$t1 = (getmicrotime($end) - getmicrotime($start));
echo "
double quotes: $t1
";
unset($a);
$start = microtime();
$b = array();
for($i=0;$i<100;$i++) {
array_push($b, 'Aaron rules!');
}
$end = microtime();
$t2 = (getmicrotime($end) - getmicrotime($start));
$t3 = $t1-$t2;
echo "single quotes: $t2
difference...: $t3
";
?>
double quotes: 0.001505970954895
single quotes .: 0.00078308582305908
difference........: 0.00072288513183594
