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POHow long would it take for a For loop to run through 1000 loops?
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copied!<p>I have a SELECT query that could return a 1000 names max - more likely to return 300-400 names.</p> <p>I would like to compare an input string to the names in the array returned by the SELECT query. </p> <p>I have two questions:</p> <ol> <li>How long would a for loop take to run through (all the 1000 names in ) the array to find if there is a matching value? AND</li> <li>Is there a way to terminate the loop as soon as a match is found? (Suppose a match is found on the 10th name, running through the rest would be a waste. It doesn't matter if there are more matches - just hitting the first one is enough for my purpose.)</li> </ol> <p>I have tried return, and exit but both don't work exactly the way I'd like. </p> <p>Here are the codes I am running to test the idea: The first php file contains the array of names </p> <pre><code><?php $names=array("R","A","V"); $arrlengths=count($names); ?> </code></pre> <p>and is included in the second file.</p> <pre><code><?php include 'test-2nd-include.php'; //the above file contains an array with three names //it also contains the length of the array in the arrlengths variable //in the test case we are using a name assigned to a variable in this file //however, when used on the registration page, it will be a value that has come through $_POST $rr = "A"; //a test variable that is initially = 0 but will be incremented if value is found in array $ohno = 0; for($xx=0;$xx<$arrlengths;$xx++) { echo "$ names [ $xx ] ", $names[$xx]; echo "<br>"; if ($names[$xx] ==$rr) { // if the value is found then the test variable is set t $ohno = 1; } } if ($ohno > 0){ echo " $rr already exists in our members list" ; } else { echo "Congratulations! $rr is still available!" ; } ?> </code></pre> <p>What I have seen is that if I use return or exit after <code>$ohno = 1;</code> the messages at the end do not get processed. If I move the <code>if ($ohno > 0){......$rr is still available!" ;}</code> into the for loop the results are really weird!</p> <p>I am sure I am missing something but after staring at this for an entire afternoon, I still cannot find a way to make the code stop running after it encounters the first match AND display the appropriate messages - both when it finds a match and when it doesn't. </p> <p>And that is the reason for the first question! Is the time I am spending trying to do this worth the saving in terms of server time/processing in the long run? After all, with a max of 1000 expected users, this code might run about 300-400 times over a period of a month or so?!?</p>

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