.. _extended_innodb_fast_index_creation:
============================ Extended Fast Index Creation
============================ Percona has implemented several
changes related to |MySQL|'s fast index creation feature. This
feature extends the ``ALTER TABLE`` command by adding a new
clause that provides online index renaming capability, that is
renaming indexes without rebuilding the whole table. Enabling
Extended Fast Index Creation
===================================== Fast index creation was
implemented in |MySQL| as a way to speed up the process of
adding or dropping indexes on tables with many rows. However,
cases have been found in which fast index creation creates an
inconsistency between |MySQL| and |InnoDB| data dictionaries.
This feature implements a session variable that enables extended
fast index creation. Besides optimizing DDL directly,
:variable:`expand_fast_index_creation` may also optimize index
access for subsequent DML statements because using it results in
much less fragmented indexes. :co