MySQL 歷史版本列表 Page47

更新時間：2011-07-06
更新細節：

What's new in this version:

Functionality added or changed:

- CMake configuration support on Linux now provides a boolean ENABLE_GCOV option to control whether to include support for gcov. 
- Client programs now display more information for SSL errors to aid in diagnosis and debugging of connection problems. 
- In the audit plugin interface, the event_class member was removed from the mysql_event_general structure and the calling sequence for the notification function changed. Originally, the second argument was a pointer to the event structure. The function now receives this information as two arguments: an event class number and a pointer to the event. Corresponding to these changes, MYSQL_AUDIT_INTERFACE_VERSION was increased to 0x0300.


Bugs fixed:
- Replication: A mistake in thread cleanup could cause a replication master to crash. 
- Replication: When using row-based replication and attribute promotion or demotion (see Section 15.4.1.6.2, “Replication of Columns Having Different Data Types”), memory allocated internally for conversion of BLOB columns was not freed afterwards. 
- Adding support for Windows authentication to libmysql introduced a link dependency on the system Secur32 library. The Microsoft Visual C++ link information was modified to pull in this library automatically. 
- In some cases, memory allocated for Query_tables_list::sroutines() was not freed properly. 
- After the fix for Bug#11889186, MAKEDATE() arguments with a year part greater than 9999 raised an assertion. 
- An assertion could be raised due to a missing NULL value check in Item_func_round::fix_length_and_dec(). 
- An assertion could be raised during two-phase commits if the binary log was used as the transaction coordinator log.
- A problem introduced in 5.5.11 caused very old (MySQL 4.0) clients to be unable to connect to the server. 
- Using CREATE EVENT IF NOT EXISTS for an event that already existed and was enabled caused multiple instances of the event to run. 
- An embedded client would abort rather than issue an error message if it issued a TEE command (T file_name) and the directory containing the file did not exist. This occurred because the wrong error handler was called. 
- On some platforms, the Incorrect value: xxx for column yyy at row zzz error produced by LOAD DATA INFILE could have an incorrect value of zzz. 
- An attempt to install nonexistent files during installation was corrected. 
- On FreeBSD 64-built builds of the embedded server, exceptions were not prevented from propagating into the embedded application.

更新時間：2011-07-06
更新細節：

What's new in this version:

Functionality added or changed:

- CMake configuration support on Linux now provides a boolean ENABLE_GCOV option to control whether to include support for gcov. 
- Client programs now display more information for SSL errors to aid in diagnosis and debugging of connection problems. 
- In the audit plugin interface, the event_class member was removed from the mysql_event_general structure and the calling sequence for the notification function changed. Originally, the second argument was a pointer to the event structure. The function now receives this information as two arguments: an event class number and a pointer to the event. Corresponding to these changes, MYSQL_AUDIT_INTERFACE_VERSION was increased to 0x0300.


Bugs fixed:
- Replication: A mistake in thread cleanup could cause a replication master to crash. 
- Replication: When using row-based replication and attribute promotion or demotion (see Section 15.4.1.6.2, “Replication of Columns Having Different Data Types”), memory allocated internally for conversion of BLOB columns was not freed afterwards. 
- Adding support for Windows authentication to libmysql introduced a link dependency on the system Secur32 library. The Microsoft Visual C++ link information was modified to pull in this library automatically. 
- In some cases, memory allocated for Query_tables_list::sroutines() was not freed properly. 
- After the fix for Bug#11889186, MAKEDATE() arguments with a year part greater than 9999 raised an assertion. 
- An assertion could be raised due to a missing NULL value check in Item_func_round::fix_length_and_dec(). 
- An assertion could be raised during two-phase commits if the binary log was used as the transaction coordinator log.
- A problem introduced in 5.5.11 caused very old (MySQL 4.0) clients to be unable to connect to the server. 
- Using CREATE EVENT IF NOT EXISTS for an event that already existed and was enabled caused multiple instances of the event to run. 
- An embedded client would abort rather than issue an error message if it issued a TEE command (T file_name) and the directory containing the file did not exist. This occurred because the wrong error handler was called. 
- On some platforms, the Incorrect value: xxx for column yyy at row zzz error produced by LOAD DATA INFILE could have an incorrect value of zzz. 
- An attempt to install nonexistent files during installation was corrected. 
- On FreeBSD 64-built builds of the embedded server, exceptions were not prevented from propagating into the embedded application.

更新時間：2011-07-05
更新細節：

What's new in this version:

Bugs fixed:

* InnoDB Storage Engine: If the server crashed while an XA transaction was prepared but not yet committed, the transaction could remain in the system after restart, and cause a subsequent shutdown to hang. 
* Partitioning: When executing a row-ordered retrieval index merge, the partitioning handler used memory from that allocated for the table, rather than that allocated to the query, causing table object memory not to be freed until the table was closed. 
* Replication: When mysqlbinlog was invoked using --base64-output=decode-row and --start-position=pos, (where pos is a point in the binary log past the format description log event), a spurious error of the type shown here was generated:
- malformed binlog: it does not contain any Format_description_log_event... 
- However, since there is nothing unsafe about not printing the format description log event, the error has been removed for this case. 
* Replication: Typographical errors appeared in the text of several replication error messages. (The word “position” was misspelled as “postion”.) 
* After the fix for Bug#11889186, MAKEDATE() arguments with a year part greater than 9999 raised an assertion. 
* An assertion could be raised due to a missing NULL value check in Item_func_round::fix_length_and_dec(). 
* In debug builds on Solaris, an assertion was raised if a reverse IP lookup with gethostbyaddr_r() failed. 
* MySQL did not build if configured with both --with-debug and --with-libedit. 
* A problem introduced in 5.1.57 caused very old (MySQL 4.0) clients to be unable to connect to the server. 
* Using CREATE EVENT IF NOT EXISTS for an event that already existed and was enabled caused multiple instances of the event to run. 
* The incorrect max_length value for YEAR values could be used in temporary result tables for UNION, leading to incorrect results. 
* In Item_func_in::fix_length_and_dec(), a Valgrind warning for uninitialized values was corrected. 
* In ROUND() calculations, a Valgrind warning for uninitialized memory was corrected. 
* Valgrind warnings caused by comparing index values to an uninitialized field were corrected. 
* LOAD DATA INFILE errors could leak I/O cache memory. 
* For LOAD DATA INFILE, multibyte character sequences could be pushed onto a stack too small to accommodate them. 
* An embedded client would abort rather than issue an error message if it issued a TEE command (T file_name) and the directory containing the file did not exist. This occurred because the wrong error handler was called. 
* On Linux, the mysql client built using the bundled libedit did not read ~/.editrc. 
* The optimizer sometimes incorrectly processed HAVING clauses for queries that did not also have an ORDER BY clause. 
* PROCEDURE ANALYZE() could leak memory for NULL results, and could return incorrect results if used with a LIMIT clause. 
* On some platforms, the Incorrect value: xxx for column yyy at row zzz error produced by LOAD DATA INFILE could have an incorrect value of zzz. 
* In MySQL 5.1 and up, if a table had triggers that used syntax supported in 5.0 but not 5.1, the table became unavailable. Now the table is marked as having broken triggers. 
* An attempt to install nonexistent files during installation was corrected. 
* On FreeBSD 64-built builds of the embedded server, exceptions were not prevented from propagating into the embedded application.

更新時間：2011-06-02
更新細節：

What's new in this version:

Bugs fixed:

- InnoDB Storage Engine: If the server crashed while an XA transaction was prepared but not yet committed, the transaction could remain in the system after restart, and cause a subsequent shutdown to hang.
- InnoDB Storage Engine: Similar problem to the foreign key error in bug #11831040 / 60196 / 60909, but with a different root cause and occurring on Mac OS X. With the setting lower_case_table_names=2, inserts into InnoDB tables covered by foreign key constraints could fail after a server restart.
- Partitioning: The internal get_partition_set() function did not take into account the possibility that a key specification could be NULL in some cases. 
- Partitioning: When executing a row-ordered retrieval index merge, the partitioning handler used memory from from that allocated for the table, rather than that allocated to the query, causing table object memory not to be freed until the table was closed.
- Replication: A spurious error malformed binlog: it does not contain any Format_description_log_event... was generated when mysqlbinlog was invoked using --base64-output=decode-row and --start-position=pos, where pos is a point in the binary log past the format description log event. However, there is nothing unsafe about not printing the format description log event, so the error has been removed for this case.
- Replication: Typographical errors appeared in the text of several replication error messages. (The word “position” was misspelled as “postion”.) 
- Assignments to NEW.var_name within triggers, where var_name had a BLOB or TEXT type, were not properly handled and produced incorrect results.
- XA COMMIT could fail to clean up the error state if it discovered that the current XA transaction had to be rolled back. Consequently, the next XA transaction could raise an assertion when it checked for proper cleanup of the previous transaction.
- An internal client macro reference was removed from the client_plugin.h header file. This reference made the file unusable.
- The server consumed memory for repeated invocation of some stored procedures, which was not released until the connection terminated.
- The server did not check for certain invalid out of order sequences of XA statements, and these sequences raised an assertion. 
- With the conversion from GNU autotools to CMake for configuring MySQL, the USE_SYMDIR preprocessor symbol was omitted. This caused failure of symbolic links (described at Section 7.11.3.1, “Using Symbolic Links”).
- The incorrect max_length value for YEAR values could be used in temporary result tables for UNION, leading to incorrect results.
- In Item_func_in::fix_length_and_dec(), a Valgrind warning for uninitialized values was corrected. 
- In ROUND() calculations, a Valgrind warning for uninitialized memory was corrected. 
- Valgrind warnings caused by comparing index values to an uninitialized field were corrected.
- LOAD DATA INFILE errors could leak I/O cache memory. 
- For LOAD DATA INFILE, multibyte character sequences could be pushed onto a stack too small to accommodate them. 
- Internal Performance Schema header files were unnecessarily installed publicly.
- On Linux, the mysql client built using the bundled libedit did not read ~/.editrc.
- The optimizer sometimes incorrectly processed HAVING clauses for queries that did not also have an ORDER BY clause.
- PROCEDURE ANALYZE() could leak memory for NULL results, and could return incorrect results if used with a LIMIT clause.
- With DISTINCT CONCAT(col,...) returned incorrect results when the arguments to CONCAT() were columns with an integer data type declared with a display width narrower than the values in the column. (For example, if an INT(1) column contain 1111.)

更新時間：2011-06-02
更新細節：

What's new in this version:

Bugs fixed:

- InnoDB Storage Engine: If the server crashed while an XA transaction was prepared but not yet committed, the transaction could remain in the system after restart, and cause a subsequent shutdown to hang.
- InnoDB Storage Engine: Similar problem to the foreign key error in bug #11831040 / 60196 / 60909, but with a different root cause and occurring on Mac OS X. With the setting lower_case_table_names=2, inserts into InnoDB tables covered by foreign key constraints could fail after a server restart.
- Partitioning: The internal get_partition_set() function did not take into account the possibility that a key specification could be NULL in some cases. 
- Partitioning: When executing a row-ordered retrieval index merge, the partitioning handler used memory from from that allocated for the table, rather than that allocated to the query, causing table object memory not to be freed until the table was closed.
- Replication: A spurious error malformed binlog: it does not contain any Format_description_log_event... was generated when mysqlbinlog was invoked using --base64-output=decode-row and --start-position=pos, where pos is a point in the binary log past the format description log event. However, there is nothing unsafe about not printing the format description log event, so the error has been removed for this case.
- Replication: Typographical errors appeared in the text of several replication error messages. (The word “position” was misspelled as “postion”.) 
- Assignments to NEW.var_name within triggers, where var_name had a BLOB or TEXT type, were not properly handled and produced incorrect results.
- XA COMMIT could fail to clean up the error state if it discovered that the current XA transaction had to be rolled back. Consequently, the next XA transaction could raise an assertion when it checked for proper cleanup of the previous transaction.
- An internal client macro reference was removed from the client_plugin.h header file. This reference made the file unusable.
- The server consumed memory for repeated invocation of some stored procedures, which was not released until the connection terminated.
- The server did not check for certain invalid out of order sequences of XA statements, and these sequences raised an assertion. 
- With the conversion from GNU autotools to CMake for configuring MySQL, the USE_SYMDIR preprocessor symbol was omitted. This caused failure of symbolic links (described at Section 7.11.3.1, “Using Symbolic Links”).
- The incorrect max_length value for YEAR values could be used in temporary result tables for UNION, leading to incorrect results.
- In Item_func_in::fix_length_and_dec(), a Valgrind warning for uninitialized values was corrected. 
- In ROUND() calculations, a Valgrind warning for uninitialized memory was corrected. 
- Valgrind warnings caused by comparing index values to an uninitialized field were corrected.
- LOAD DATA INFILE errors could leak I/O cache memory. 
- For LOAD DATA INFILE, multibyte character sequences could be pushed onto a stack too small to accommodate them. 
- Internal Performance Schema header files were unnecessarily installed publicly.
- On Linux, the mysql client built using the bundled libedit did not read ~/.editrc.
- The optimizer sometimes incorrectly processed HAVING clauses for queries that did not also have an ORDER BY clause.
- PROCEDURE ANALYZE() could leak memory for NULL results, and could return incorrect results if used with a LIMIT clause.
- With DISTINCT CONCAT(col,...) returned incorrect results when the arguments to CONCAT() were columns with an integer data type declared with a display width narrower than the values in the column. (For example, if an INT(1) column contain 1111.)

更新時間：2011-05-08
更新細節：

What's new in this version:

Bugs fixed:

- InnoDB Storage Engine: Replication: Trying to update a column, previously set to NULL, of an InnoDB table with no primary key caused replication to fail with Can't find record in 'table' on the slave. 
- InnoDB Storage Engine: The server could halt if InnoDB interpreted a very heavy I/O load for 15 minutes or more as an indication that the server was hung. This change fixes the logic that measures how long InnoDB threads were waiting, which formerly could produce false positives. 
- InnoDB Storage Engine: With the setting lower_case_table_names=2, inserts into InnoDB tables covered by foreign key constraints could fail after a server restart. 
- Replication: Using the --server-id option with mysqlbinlog could cause format description log events to be filtered out of the binary log, leaving mysqlbinlog unable to read the remainder of the log. Now such events are always read without regard to the value of this option.
- As part of the the fix for this problem, mysqlbinlog now also reads rotate log events without regard to the value of --server-id. 
- On Windows, the server rejected client connections if no DNS server was available. 
- mysql_upgrade did not properly upgrade the authentication_string column of the mysql.user table.
- InnoDB invoked some zlib functions without proper initialization. 
- Comparison of a DATETIME stored program variable and NOW() led to an “Illegal mix of collations error” when character_set_connection was set to utf8. (Bug #60625, Bug #11926811)
- Selecting from a view for which the definition included a HAVING clause failed with an error:
* 1356: View '...' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them
- CREATE TABLE syntax permits specification of a STORAGE {DEFAULT|DISK|MEMORY} option. However, this value was not written to the .frm file, so that a subsequent CREATE TABLE ... LIKE for the table did not include that option.
* Also, ALTER TABLE of a table that had a tablespace incorrectly destroyed the tablespace. 
- The server permitted max_allowed_packet to be set lower than net_buffer_length, which does not make sense because max_allowed_packet is the upper limit on net_buffer_length values. Now a warning occurs and the value remains unchanged. 
- A missing variable initialization for Item_func_set_user_var objects could cause an assertion to be raised. 
- When the server was started with the --skip-innodb option, it initialized the have_innodb system variable to YES rather than DISABLED. 
- In Item_func_month::val_str(), a Valgrind warning for a too-late NULL value check was corrected. 
- In Item::get_date, a Valgrind warning for a missing NULL value check was corrected. 
- In extract_date_time(), a Valgrind warning for a missing end-of-string check was corrected. 
- In string context, the MIN() and MAX() functions did not take into account the unsignedness of a BIGINT UNSIGNED argument. 
- In Item_func::val_decimal, a Valgrind warning for a missing NULL value check was corrected. 
- In Item_func_str_to_date::val_str, a Valgrind warning for an uninitialized variable was corrected. 
- An assertion could be raised in Item_func_int_val::fix_num_length_and_dec() due to overflow for geometry functions. 
- With prepared statements, the server could attempt to send result set metadata after the table had been closed. 
- With lower_case_table_names=2, resolution of objects qualified by database names could fail. 
- SHOW EVENTS did not always show events from the correct database. 

更新時間：2011-05-08
更新細節：

What's new in this version:

Bugs fixed:

- InnoDB Storage Engine: Replication: Trying to update a column, previously set to NULL, of an InnoDB table with no primary key caused replication to fail with Can't find record in 'table' on the slave. 
- InnoDB Storage Engine: The server could halt if InnoDB interpreted a very heavy I/O load for 15 minutes or more as an indication that the server was hung. This change fixes the logic that measures how long InnoDB threads were waiting, which formerly could produce false positives. 
- InnoDB Storage Engine: With the setting lower_case_table_names=2, inserts into InnoDB tables covered by foreign key constraints could fail after a server restart. 
- Replication: Using the --server-id option with mysqlbinlog could cause format description log events to be filtered out of the binary log, leaving mysqlbinlog unable to read the remainder of the log. Now such events are always read without regard to the value of this option.
- As part of the the fix for this problem, mysqlbinlog now also reads rotate log events without regard to the value of --server-id. 
- On Windows, the server rejected client connections if no DNS server was available. 
- mysql_upgrade did not properly upgrade the authentication_string column of the mysql.user table.
- InnoDB invoked some zlib functions without proper initialization. 
- Comparison of a DATETIME stored program variable and NOW() led to an “Illegal mix of collations error” when character_set_connection was set to utf8. (Bug #60625, Bug #11926811)
- Selecting from a view for which the definition included a HAVING clause failed with an error:
* 1356: View '...' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them
- CREATE TABLE syntax permits specification of a STORAGE {DEFAULT|DISK|MEMORY} option. However, this value was not written to the .frm file, so that a subsequent CREATE TABLE ... LIKE for the table did not include that option.
* Also, ALTER TABLE of a table that had a tablespace incorrectly destroyed the tablespace. 
- The server permitted max_allowed_packet to be set lower than net_buffer_length, which does not make sense because max_allowed_packet is the upper limit on net_buffer_length values. Now a warning occurs and the value remains unchanged. 
- A missing variable initialization for Item_func_set_user_var objects could cause an assertion to be raised. 
- When the server was started with the --skip-innodb option, it initialized the have_innodb system variable to YES rather than DISABLED. 
- In Item_func_month::val_str(), a Valgrind warning for a too-late NULL value check was corrected. 
- In Item::get_date, a Valgrind warning for a missing NULL value check was corrected. 
- In extract_date_time(), a Valgrind warning for a missing end-of-string check was corrected. 
- In string context, the MIN() and MAX() functions did not take into account the unsignedness of a BIGINT UNSIGNED argument. 
- In Item_func::val_decimal, a Valgrind warning for a missing NULL value check was corrected. 
- In Item_func_str_to_date::val_str, a Valgrind warning for an uninitialized variable was corrected. 
- An assertion could be raised in Item_func_int_val::fix_num_length_and_dec() due to overflow for geometry functions. 
- With prepared statements, the server could attempt to send result set metadata after the table had been closed. 
- With lower_case_table_names=2, resolution of objects qualified by database names could fail. 
- SHOW EVENTS did not always show events from the correct database. 

更新時間：2011-05-07
更新細節：

What's new in this version:

Bugs fixed:

- InnoDB Storage Engine: Replication: Trying to update a column, previously set to NULL, of an InnoDB table with no primary key caused replication to fail with Can't find record in 'table' on the slave. (Bug #11766865, Bug #60091)
- InnoDB Storage Engine: The server could halt if InnoDB interpreted a very heavy I/O load for 15 minutes or more as an indication that the server was hung. This change fixes the logic that measures how long InnoDB threads were waiting, which formerly could produce false positives. (Bug #11877216, Bug #11755413, Bug #47183)
- Replication: Using the --server-id option with mysqlbinlog could cause format description log events to be filtered out of the binary log, leaving mysqlbinlog unable to read the remainder of the log. Now such events are always read without regard to the value of this option.
* As part of the the fix for this problem, mysqlbinlog now also reads rotate log events without regard to the value of --server-id. (Bug #11766427, Bug #59530)
- Partitioning: A problem with a previous fix for poor performance of INSERT ON DUPLICATE KEY UPDATE statements on tables having many partitions caused the handler function for reading a row from a specific index to fail to store the ID of the partition last used. This caused some statements to fail with Can't find record errors. (Bug #59297, Bug #11766232)
- InnoDB invoked some zlib functions without proper initialization. (Bug #11849231)
- Two unused test files in storage/ndb/test/sql contained incorrect versions of the GNU Lesser General Public License. The files and the directory containing them have been removed. (Bug #11810224)
- Selecting from a view for which the definition included a HAVING clause failed with an error:
* 1356: View '...' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them
- The server permitted max_allowed_packet to be set lower than net_buffer_length, which does not make sense because max_allowed_packet is the upper limit on net_buffer_length values. Now a warning occurs and the value remains unchanged. (Bug #59959, Bug #11766769)
- The server read one byt

更新時間：2011-04-08
更新細節：

What's new in this version:

Bugs fixed:

- Partitioning: A problem with a previous fix for poor performance of INSERT ON DUPLICATE KEY UPDATE statements on tables having many partitions caused the handler function for reading a row from a specific index to fail to store the ID of the partition last used. This caused some statements to fail with Can't find record errors. 
- An assertion was raised if an XA COMMIT was issued when an XA transaction had already encountered an error (such as a deadlock) that required the transaction to be rolled back. 
- On some systems, debug builds of comp_err.c could fail due to an uninitialized variable. 
- The server read one byte too many when trying to process an XML string lacking a closing quote (') or double quote (") character used as an argument for UpdateXML() or ExtractValue(). 
- Attempting to create a spatial index on a CHAR column longer than 31 bytes led to an assertion failure if the server was compiled with safemutex support. 
- Aggregation followed by a subquery could produce an incorrect result. 
- An incorrect character set pointer passed to my_strtoll10_mb2() caused an assertion to be raised. 
- mysqldump did not quote database names in ALTER DATABASE statements in its output, which could cause an error at reload time for database names containing a dash. 
- The MYSQL_HOME environment variable was being ignored. 
- If a multiple-table update updated a row through two aliases and the first update physically moved the row, the second update failed to locate the row. This resulted in different errors depending on storage engine, although these errors did not accurately describe the problem:
- MyISAM: Got error 134 from storage engine
- InnoDB: Can't find record in 'tbl'
For MyISAM, which is nontransactional, the update executed first was performed but the second was not. In addition, for two equal multiple-table update statements, one could succeed and the other fail depending on whether the record actually moved, which is inconsistent.
Now such an update returns an error if it will update a table through multiple aliases, and perform an update that may physically more the row in at least one of these aliases. 
- SHOW WARNINGS output following EXPLAIN EXTENDED could include unprintable characters. 
- When CASE ... WHEN arguments had different character sets, 8-bit values could be referenced as utf16 or utf32 values, causing an assertion to be raised. 
- Bitmap functions used in one thread could change bitmaps used by other threads, causing an assertion to be raised.

更新時間：2011-04-08
更新細節：

What's new in this version:

Bugs fixed:

- Partitioning: A problem with a previous fix for poor performance of INSERT ON DUPLICATE KEY UPDATE statements on tables having many partitions caused the handler function for reading a row from a specific index to fail to store the ID of the partition last used. This caused some statements to fail with Can't find record errors. 
- An assertion was raised if an XA COMMIT was issued when an XA transaction had already encountered an error (such as a deadlock) that required the transaction to be rolled back. 
- On some systems, debug builds of comp_err.c could fail due to an uninitialized variable. 
- The server read one byte too many when trying to process an XML string lacking a closing quote (') or double quote (") character used as an argument for UpdateXML() or ExtractValue(). 
- Attempting to create a spatial index on a CHAR column longer than 31 bytes led to an assertion failure if the server was compiled with safemutex support. 
- Aggregation followed by a subquery could produce an incorrect result. 
- An incorrect character set pointer passed to my_strtoll10_mb2() caused an assertion to be raised. 
- mysqldump did not quote database names in ALTER DATABASE statements in its output, which could cause an error at reload time for database names containing a dash. 
- The MYSQL_HOME environment variable was being ignored. 
- If a multiple-table update updated a row through two aliases and the first update physically moved the row, the second update failed to locate the row. This resulted in different errors depending on storage engine, although these errors did not accurately describe the problem:
- MyISAM: Got error 134 from storage engine
- InnoDB: Can't find record in 'tbl'
For MyISAM, which is nontransactional, the update executed first was performed but the second was not. In addition, for two equal multiple-table update statements, one could succeed and the other fail depending on whether the record actually moved, which is inconsistent.
Now such an update returns an error if it will update a table through multiple aliases, and perform an update that may physically more the row in at least one of these aliases. 
- SHOW WARNINGS output following EXPLAIN EXTENDED could include unprintable characters. 
- When CASE ... WHEN arguments had different character sets, 8-bit values could be referenced as utf16 or utf32 values, causing an assertion to be raised. 
- Bitmap functions used in one thread could change bitmaps used by other threads, causing an assertion to be raised.