Why does my foreach loop display doubled data when using `mysql_fetch_array`?

Doubled Results in Array (mysql_fetch_array)

The given code encounters an issue where the foreach loop displays doubled data due to the way mysql_fetch_array operates. By default, it assigns both numeric and associative indexes to each element in the result array. This effect can be observed in the print_r output, where both indexes (0, 1, 2, etc.) and their corresponding keys (id, department_id, name, etc.) appear.

To resolve this issue, you can specify the type of indexes you want in the mysql_fetch_array function call. By passing MYSQL_NUM as the second parameter, you can retrieve an array with only numeric keys. Alternatively, MYSQL_ASSOC will return an array with only associative keys.

<code class="php">// Get numeric keys only
$query_result_array = mysql_fetch_array($query_result, MYSQL_NUM);

// Get associative keys only
$query_result_array = mysql_fetch_array($query_result, MYSQL_ASSOC);</code>

You can also use the mysql_fetch_row and mysql_fetch_assoc functions, which specifically return numeric or associative arrays, respectively:

<code class="php">// Get numeric keys only
$query_result_array = mysql_fetch_row($query_result);

// Get associative keys only
$query_result_array = mysql_fetch_assoc($query_result);</code>

By utilizing these options, you can avoid duplicated data in your foreach loop and ensure that the resulting array contains the indexes and values that you need.

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