MysqliDbConnection::getIndexName

public function getIndexName($tableName, array $arColumns, $strict = false)
{
	if (!is_array($arColumns) || empty($arColumns))
		return null;

	$tableName = preg_replace("/[^a-z0-9_]+/i", "", $tableName);
	$tableName = trim($tableName);

	$rs = $this->query("SHOW INDEX FROM `".$this->getSqlHelper()->forSql($tableName)."`");
	if (!$rs)
		return null;

	$arIndexes = array();
	while ($ar = $rs->fetch())
		$arIndexes[$ar["Key_name"]][$ar["Seq_in_index"] - 1] = $ar["Column_name"];

	$strColumns = implode(",", $arColumns);
	foreach ($arIndexes as $Key_name => $arKeyColumns)
	{
		ksort($arKeyColumns);
		$strKeyColumns = implode(",", $arKeyColumns);
		if ($strict)
		{
			if ($strKeyColumns === $strColumns)
				return $Key_name;
		}
		else
		{
			if (substr($strKeyColumns, 0, strlen($strColumns)) === $strColumns)
				return $Key_name;
		}
	}

	return null;
}