Why Does Echoing a MySQL Query in PHP Return \'Resource id #6\' Instead of a String?

Echoing MySQL Query Results as Strings

In PHP, a common task is to retrieve data from a MySQL database and display it on a web page. However, when attempting to echo the result of a MySQL query, you may encounter the error "Resource id #6" instead of the expected string.

Understanding Resource IDs

When executing a MySQL query using functions like mysql_query(), PHP returns a resource ID rather than the actual result data. This resource ID is a temporary reference to the query result, which can be used to further manipulate the data.

Fetching the Actual Result

To retrieve the actual result string, you need to use a fetch function. The most common fetch function is mysql_fetch_assoc(), which returns an associative array where the keys are the column names and the values are the corresponding values from the database row.

Example Code

The following modified code uses mysql_fetch_assoc() to fetch the result and echo the "time_delta" column as the intended string:

<code class="php">$result = mysql_query(sprintf("SELECT TIMEDIFF(NOW(), '%s') as time_delta", $row['fecha']));
if($result){
  $data = mysql_fetch_assoc($result);
  echo $data['time_delta'];
}</code>

Alternative Approaches

While the mysql_query() and mysql_fetch_assoc() functions are still widely used, it's important to note that they are deprecated and replaced by newer and more secure methods. Consider using PDO with PDO_mysql or mysqli instead for database access in new projects.

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