mysql_fetch_field

Description

Returns an object containing field information.

mysql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retrieved by mysql_fetch_field() is retrieved.

The properties of the object are:

• name - column name

• table - name of the table the column belongs to

• max_length - maximum length of the column

• not_null - 1 if the column cannot be NULL

• primary_key - 1 if the column is a primary key

• unique_key - 1 if the column is a unique key

• multiple_key - 1 if the column is a non-unique key

• numeric - 1 if the column is numeric

• blob - 1 if the column is a BLOB

• type - the type of the column

• unsigned - 1 if the column is unsigned

• zerofill - 1 if the column is zero-filled

Example 1. mysql_fetch_field() example <?php $conn = mysql_connect('localhost:3306', 'user', 'password'); if (!$conn) {     die('Could not connect: ' . mysql_error()); } mysql_select_db('database'); $result = mysql_query('select * from table'); if (!$result) {     die('Query failed: ' . mysql_error()); } /* get column metadata */ $i = 0; while ($i < mysql_num_fields($result)) {     echo "Information for column $i:<br />\n";     $meta = mysql_fetch_field($result, $i);     if (!$meta) {         echo "No information available<br />\n";     }     echo "<pre> blob:         $meta->blob max_length:   $meta->max_length multiple_key: $meta->multiple_key name:         $meta->name not_null:     $meta->not_null numeric:      $meta->numeric primary_key:  $meta->primary_key table:        $meta->table type:         $meta->type unique_key:   $meta->unique_key unsigned:     $meta->unsigned zerofill:     $meta->zerofill </pre>";     $i++; } mysql_free_result($result); ?>

See also mysql_field_seek().