function addUniqueKey($table, $fields, $name = '', $tablespace = '')
{
if (!is_array($fields) || sizeof($fields) == 0) {
return -1;
}
$f_schema = $this->_schema;
$this->fieldClean($f_schema);
$this->fieldClean($table);
$this->fieldArrayClean($fields);
$this->fieldClean($name);
$this->fieldClean($tablespace);
$sql = "ALTER TABLE \"{$f_schema}\".\"{$table}\" ADD ";
if ($name != '') {
$sql .= "CONSTRAINT \"{$name}\" ";
}
$sql .= "UNIQUE (\"" . join('","', $fields) . "\")";
if ($tablespace != '' && $this->hasTablespaces()) {
$sql .= " USING INDEX TABLESPACE \"{$tablespace}\"";
}
return $this->execute($sql);
}