Important Change: Security Fix: Additional corrections were made for the symlink-related privilege problem originally addressed in MySQL 5.0.60. The original fix did not correctly handle the data directory path name if it contained symlinked directories in its path, and the check was made only at table-creation time, not at table-opening time later. (Bug#32167, CVE-2008-2079)
See also Bug#39277.
There were some problems using
hook functions on Windows that automatically do global and
per-thread initialization for
Per-thread initialization: MySQL internally counts the
number of active threads, which causes a delay in
my_end() if not all threads have
exited. But there are threads that can be started either by
Windows internally (often in TCP/IP scenarios) or by users.
Those threads do not necessarily use
libmysql.dll functionality but still
contribute to the open-thread count. (One symptom is a
five-second delay in times for PHP scripts to finish.)
WSAStartup that itself loads DLLs and
can lead to a deadlock in the Windows loader.
To correct these problems, DLL initialization code now is not
libmysql.dll by default. To
obtain the previous behavior (DLL initialization code will be
called), set the
variable to any value. This variable exists only to prevent
breakage of existing Windows-only applications that do not call
mysql_thread_init() and work
okay today. Use of
discouraged and is removed in MySQL 6.0.
SHOW STATUS took a lot of CPU
time for calculating the value of the
status variable. Now this variable is calculated and included in
the output of
SHOW STATUS only if
UNIV_DEBUG symbol is defined at MySQL
In connection with view creation, the server created
arc directories inside database directories
and maintained useless copies of
there. Creation and renaming procedures of those copies as well
as creation of
arc directories has been
This change does cause a problem when downgrading to older server versions which manifests itself under these circumstances:
Create a view
v_orig in MySQL 5.0.72 or
Rename the view to
v_new and then back to
Downgrade to an older 5.0.x server and run mysql_upgrade.
Try to rename
v_new again. This operation fails.
As a workaround to avoid this problem, use either of these approaches:
Dump your data using mysqldump before downgrading and reload the dump file after downgrading.
Instead of renaming a view after the downgrade, drop it and recreate it.