Implements hook_field_schema().
function email_field_schema($field) {
$columns = array(
'value' => array(
'type' => 'varchar',
// The maximum length of an e-mail address is 254 characters. RFC 3696
// specifies a total length of 320 characters, but mentions that
// addresses longer than 256 characters are not normally useful. Erratum
// 1690 was then released which corrected this value to 254 characters.
// @see http://tools.ietf.org/html/rfc3696#section-3
// @see http://www.rfc-editor.org/errata_search.php?rfc=3696&eid=1690
'length' => 254,
'not null' => FALSE,
),
);
return array(
'columns' => $columns,
);
}