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POPHP substr() REALLY slow when not taking first part of string
 

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  1. POPHP substr() REALLY slow when not taking first part of string
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    <p>I have a text file that has about 5,000 lines with each line being about 200 characters long. Each line actually contains 6 different pieces of data that I've been using <code>substr()</code> to break apart. For example, on each line, characters 0 - 10 contain the Client#, characters 10-20 contain the Matter#, etc. This is all well and good and was running faster than I even needed it to.</p> <p>My problems arose when I was told by my boss that the client number has 4 leading zeros and they need to be stripped off. So I thought, no problem - I just changed my first <code>substr()</code> function from <code>substr(0, 10)</code> (start at 0 and take 10 characters) and changed it to <code>substr(4, 6)</code> (starting at the 4th character and just taking 6) which will skip the 4 leading zeros and I'll be good to go.</p> <p>However, when I changed the <code>substr(0, 10)</code> to <code>substr(4,6)</code> the process grinds to a halt and takes <strong>forever</strong> to complete. Why is this?</p> <p>Here is a snippet from my code:</p> <pre><code>// open the file $file_matters = fopen($varStoredIn_matters,"r") or exit("Unable to open file!"); // run until the end of the file while(!feof($file_matters)) { // place current line in temp variable $tempLine_matters = fgets($file_matters); // increment the matters line count $linecount_matters++; // break up each column $clientID = trim(substr($tempLine_matters, 0, 10)); // THIS ONE WORKS FINE //$clientID = trim(substr($tempLine_matters, 4, 6)); // THIS ONE MAKES THE PROCESS GRIND TO A HALT!! $matterID = trim(substr($tempLine_matters, 10, 10)); //$matterID = trim(substr($tempLine_matters, 15, 5)); $matterName = trim(substr($tempLine_matters, 20, 80)); $subMatterName = trim(substr($tempLine_matters, 100, 80)); $dateOpen = trim(substr($tempLine_matters, 180, 10)); $orgAttorney = trim(substr($tempLine_matters, 190, 3)); $bilAttorney = trim(substr($tempLine_matters, 193, 3)); $resAttorney = trim(substr($tempLine_matters, 196, 3)); //$tolCode = trim(substr($tempLine_matters, 200, 3)); $tolCode = trim(substr($tempLine_matters, 200, 3)); $dateClosed = trim(substr($tempLine_matters, 203, 10)); // just does an insert into the DB using the variables above } </code></pre>
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    1. USFastTrack
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    1. COAre you sure it's that? I.e. will it work for smaller data file? What is an error? Time limit?
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      1. POPHP substr() REALLY slow when not taking first part of string
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    2. COI cannot understand that. According to implementation it shouldn't make a real difference?
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      1. POPHP substr() REALLY slow when not taking first part of string
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    3. CO@AlmaDoMundo I'm almost positive it's that - smaller data files (I.e 200 lines) process with no problem. I get timed out at about 2 minutes since that is the max execution time set on our server in our PHP config. If I change the `substr(4, 6)` back to `substr(0, 10)` it runs in about 3 seconds with 5,000 lines.
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