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    <ol> <li><p>Have you profiled this query?</p> <p>"SELECT * FROM it_raw WHERE perfID = '".addslashes($feed_array['16'][$counter])."'"</p> <p>Because you run it 28000 times.. so unless it is REALLY quick, it will cause you a head ache. Use the <a href="http://dev.mysql.com/doc/refman/5.0/en/explain.html" rel="nofollow noreferrer">EXPLAIN syntax</a> and add an appropriate index if needed.</p> <p><strong>EDIT</strong>: With profile, I mean that you should try to use EXPLAIN on the mysql-prompt to see what execution plan the MySQL Query Optimizer suggests for this query. I.e, on the prompt, run:</p> <pre><code>EXPLAIN SELECT * FROM it_raw WHERE perfID = 426; # Change this id to something existing and valid </code></pre> <p>What you want to see is that it is using an index, and ONLY an index. If you don't understand the output, copy and paste it here so can I go through it with you.</p> <p><strong>UPDATE</strong>: As you can see, it takes 0.07 seconds for EVERY row in your data array, plus the time to actually query the database, transfer the result etc. This is roughly 28000 * 0.07 = 1960 seconds, or 32 minutes, just to check if the data exists or not. You need to come up with another way of checking if the data already exists... One, very simple optimization might be: </p> <pre><code>EXPLAIN SELECT perfId FROM it_raw WHERE perfID = 210968; </code></pre> <p>This way, you can use the index on perfId and don't need to visit the table</p></li> <li><p>If it is possible, try to avoid quering the database for each run in the loop. Perhaps it is possible to fetch the ids from the database into a big array of ids that will fit in PHP memory? This will be MUCH quicker than quering the database for every row in your big data array.</p></li> </ol>
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    1. POSpeed up this code - PHP/SQL - Short Code but takes incredibly long at the moment
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    1. USPatrikAkerstrand
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    1. COCan you explain what you mean by profiled? (echo micro time before and after?)
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      1. USShadi Almosri
    2. COadded an explain output (although using phpmyadmin - not sure if it effects what you see [i can use shell if needed]) in my question
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      1. USShadi Almosri
    3. COUpdated with shell out put and time...
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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