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POsave random data to db without duplication - php
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  1. POsave random data to db without duplication - php
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    copied!<p>It is an examination system and I made a random question, my problem is how to save it and identify if it is already saved in the database.<br> Below is the code for the random, why after I click the next even it doesn't have an action in the FORM it post undefined index "sub" BUT i already declare it at the top. How to save data, if it is random and avoid to duplicate the saved data?</p> <pre><code>&lt;? $exam_id = $_SESSION['examreference_id']; $sub_id = $_GET['sub']; $count=0; $con = mysql_connect("localhost","root",""); if(!$con) { die('Could not connect:'. mysql_error()); } mysql_select_db("db_compre",$con); $result2 = mysql_query("SELECT * FROM examquestion_table WHERE examreference_id = '$exam_id' AND subjectreference_id = '$sub_id'"); while($info2 = mysql_fetch_array($result2)) { $count++; } mysql_close($con);?&gt; &lt;tr&gt; &lt;td colspan = "2"&gt; &lt;? $con = mysql_connect("localhost","root",""); if(!$con) { die('Could not connect:'. mysql_error()); } mysql_select_db("db_compre",$con); $result = mysql_query("SELECT * FROM examquestion_table WHERE examreference_id = '$exam_id' AND subjectreference_id = '$sub_id' ORDER BY RAND() LIMIT 1"); while($info = mysql_fetch_array($result)) { echo "&lt;tr&gt;&lt;td &gt;&lt;label&gt;" . " Your time limit is ".$info['totalTime'] ."&amp;nbsp&amp;nbsp". "second(s)" . "&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; echo "&lt;tr&gt;&lt;td &gt;&lt;label&gt;" . $info['question_data'] . "&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; echo "&lt;tr&gt;&lt;td colspan ='2'&gt;&lt;hr size = '5' color = 'orange'&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;"; echo "&lt;tr&gt;&lt;td colspan = '2'&gt;&lt;input type = 'checkbox' name='answer' onClick='javascript:checkone(0)' value = '100'&gt;&lt;label&gt;". $info['choice1_data'] ."&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; echo "&lt;tr&gt;&lt;td colspan = '2'&gt;&lt;input type = 'checkbox' name='answer' onClick='javascript:checkone(1)' value = '100'&gt;&lt;label&gt;". $info['choice2_data'] ."&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; echo "&lt;tr&gt;&lt;td colspan = '2'&gt;&lt;input type = 'checkbox' name='answer' onClick='javascript:checkone(2)' value = '100'&gt;&lt;label&gt;". $info['choice3_data'] ."&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; echo "&lt;tr&gt;&lt;td colspan = '2'&gt;&lt;input type = 'checkbox' name='answer' onClick='javascript:checkone(3)' value = '100'&gt;&lt;label&gt;". $info['choice4_data'] ."&lt;/label&gt;&lt;/td&gt;&lt;/tr&gt;"; } mysql_close($con);?&gt; </code></pre>
 

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