Why does \"mysql_fetch_array() expects parameter 1 to be resource problem\" error occur, and how to resolve it?

"Mysql_fetch_array() expects parameter 1 to be resource problem [duplicate]" - Understanding and Resolving the Error

The error "mysql_fetch_array() expects parameter 1 to be resource problem" arises when the mysql_fetch_array() function does not receive a valid resource as the first argument. This typically occurs when the preceding mysql_query() call fails to retrieve data from the database.

To resolve this error, it is crucial to perform error checking after the mysql_query() call. The following example demonstrates how to add error checking to the provided code:

<br>$result = mysql_query("SELECT * FROM student WHERE IDNO=" . $_GET['id']);<br>if (!$result) { // Add this error checking.</p>
<pre class="brush:php;toolbar:false">die('Invalid query: ' . mysql_error());

}

When mysql_query() fails, it returns false, a boolean value. If you pass it to mysql_fetch_array(), expecting a mysql result object, you will encounter the stated error.

Here's the rewritten code with error checking:

<br>$con = mysql_connect("localhost", "root", "nitoryolai123$%^");<br>if (!$con) {</p>
<pre class="brush:php;toolbar:false">die('Could not connect: ' . mysql_error());

}

mysql_select_db("school", $con);
$result = mysql_query("SELECT * FROM student WHERE IDNO=" . $_GET['id']);
if (!$result) {

die('Invalid query: ' . mysql_error());

}

while ($row = mysql_fetch_array($result)) {

?>
<table class="a" border="0" align="center" cellpadding="0" cellspacing="1" bgcolor="#D3D3D3">
    <tr>
        <form name="formcheck" method="get" action="updateact.php" onsubmit="return formCheck(this);">
            <td>
                <table border="0" cellpadding="3" cellspacing="1" bgcolor="">
                    <tr>
                        <td colspan="16" height="25" style="background:#5C915C; color:white; border:white 1px solid; text-align: left"><strong><font size="2">Update Students</font></strong></td>
                    </tr>
                    <tr>
                        <td width="30" height="35"><font size="2">*I D Number:</font></td>
                        <td width="30"><input name="idnum" onkeypress="return isNumberKey(event)" type="text" maxlength="5" id='numbers' value="<?php echo $_GET['id']; ?>" /></td>
                    </tr>
                    <tr>
                        <td width="30" height="35"><font size="2">*Year:</font></td>
                        <td width="30"><input name="yr" onkeypress="return isNumberKey(event)" type="text" maxlength="5" id='numbers' value="<?php echo $row["YEAR"]; ?>" /></td>
                    </tr>
                </table>
            </td>
        </form>
    </tr>
</table>
<?php

}

By incorporating error checking into your code, you can now identify and handle potential database retrieval failures effectively, preventing the "mysql_fetch_array() expects parameter 1 to be resource problem" error.

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