Why Does \"mysql_fetch_array() expects parameter 1 to be resource\" Error Occur?

Issue: Understanding "mysql_fetch_array() expects parameter 1 to be resource problem" Error

As mentioned in the potential duplicate provided, the error "mysql_fetch_array() expects parameter 1 to be resource problem" occurs when you attempt to use mysql_fetch_array() on a variable that is not a valid MySQL result resource.

Answer:

In your code, the issue arises from the mysql_query() call:

<code class="php">$result = mysql_query("SELECT * FROM student WHERE IDNO=".$_GET['id']);</code>

You should add error checking after the mysql_query() call to confirm that the query executed successfully. Here's the modified code:

<code class="php">$result = mysql_query("SELECT * FROM student WHERE IDNO=".$_GET['id']);
if (!$result) {
    die('Invalid query: ' . mysql_error());
}</code>

If mysql_query() fails, it returns false (a boolean value), which will cause the problem with mysql_fetch_array() because it expects a mysql result object.

Now, you can safely use mysql_fetch_array($result) to iterate through the results. Remember to add similar error checking for other MySQL functions.

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