As noted in
Section 8.6, “Controlling Optimizer Statistics Estimation”,
the InnoDB Plugin allows you to control the way in which
InnoDB gathers information about the number of distinct values
in an index key. A related parameter,
innodb_stats_on_metadata, has existed since MySQL release
5.1.17 to control whether or not InnoDB performs statistics
gathering when metadata statements are executed. See the MySQL
InnoDB Startup Options and System Variables for details.
Beginning with release 1.0.2 of the InnoDB Plugin, it is
possible to change the setting of
dynamically at runtime with the command
0). Changing this
setting requires the
SUPER privilege and
immediately affects the operation of all connections.