Beginning with MySQL 5.6.10, MySQL Enterprise Edition is available for MySQL 5.6. Specifically, MySQL Enterprise 5.6.10 includes these components previously available only in MySQL 5.5: MySQL Enterprise Security (PAM and Windows authentication plugins), MySQL Enterprise Audit, and MySQL Thread Pool. For information about these features, see MySQL Enterprise Edition. To learn more about commercial products, see https://www.mysql.com/products/.
Known limitations of this release:
On Microsoft Windows, when using the MySQL Installer to install MySQL Server 5.6.10 on a host with an existing MySQL Server of a different version (such as 5.5.30), that also has a different license (community versus commercial), you must first update the license type of the existing MySQL Server. Otherwise, MySQL Installer will remove MySQL Server(s) with different licenses from the one you chose with MySQL Server 5.6.10.
On Microsoft Windows 8, updating a community release to a commercial release requires you to manually restart the MySQL service after the update.
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The following changes were made to the sandbox mode that the server uses to handle client connections for accounts with expired passwords:
There is a new
disconnect_on_expired_password
system variable (default: enabled). This controls how the server treats expired-password accounts.-
Two flags were added to the C API client library:
MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS
formysql_options()
andCLIENT_CAN_HANDLE_EXPIRED_PASSWORDS
formysql_real_connect()
. Each flag enables a client program to indicate whether it can handle sandbox mode for accounts with expired passwords.MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS
is enabled for mysqltest unconditionally, for mysql in interactive mode, and for mysqladmin if the first command ispassword
.
For more information about how the client-side flags interact with
disconnect_on_expired_password
, see Server Handling of Expired Passwords. (Bug #67568, Bug #15874023)
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InnoDB: When compressed tables were used, the calculation to compute memory usage within the buffer pool was complex because the compressed pages could be smaller than 16KB or the user-specified page size. Although this information can be retrieved from the
INFORMATION_SCHEMA.INNODB_BUFFER_PAGE
table, that operation is expensive. The following new status variables help to simplify calculations involving buffer pool memory usage:Innodb_buffer_pool_bytes_data
, to supplementInnodb_buffer_pool_pages_data
.Innodb_buffer_pool_bytes_dirty
, to supplementInnodb_buffer_pool_pages_dirty
.
(Bug #15842637)
Replication: An
Auto_Position
column has been added to the output generated bySHOW SLAVE STATUS
. The value of this column shows whether replication autopositioning is in use. If autopositioning is enabled—that is, ifMASTER_AUTO_POSITION = 1
was set by the last successfulCHANGE MASTER TO
statement that was executed on the slave—then the column's value is 1; if not, then the value is 0. (Bug #15992220)In RPM packages built for Unbreakable Linux Network,
libmysqld.so
now has a version number. (Bug #15972480)Error messages for
ALTER TABLE
statement using aLOCK
orALGORITHM
value not supported for the given operation were very generic. The server now produces more informative messages. (Bug #15902911)If a client with an expired password connected but
old_passwords
was not the value required to select the password hashing format appropriate for the client account, there was no way for the client to determine the proper value. Now the server automatically sets the sessionold_passwords
value appropriately for the account authentication method. For example, if the account uses thesha256_password
authentication plugin, the server setsold_passwords=2
. (Bug #15892194)The
validate_password_policy_number
system variable was renamed tovalidate_password_policy
. (Bug #14588121)In JSON-format
EXPLAIN
output, theattached_condition
information for subqueries now includesselect#
to indicate the relative order of subquery execution. (Bug #13897507)
Important Change; Replication: The lettercasing used for displaying UUIDs in global transaction identifiers was inconsistent. Now, all GTID values use lowercase, including those shown in the
Retrieved_Gtid_Set
andExecuted_Gtid_Set
columns from the output ofSHOW SLAVE STATUS
. (Bug #15869441)Performance; InnoDB: Some data structures related to undo logging could be initialized unnecessarily during a query, although they were only needed under specific conditions. (Bug #14676084)
Performance; InnoDB: Optimized read operations for compressed tables by skipping redundant tests. The check for whether any related changes needed to be merged from the insert buffer was being called more often than necessary. (Bug #14329288, Bug #65886)
Performance; InnoDB: Immediately after a table was created, a query against it would not use a Loose Index Scan. The same query might use a Loose Index Scan following an
ALTER TABLE
on the table. The fix improves the accuracy of the cost estimate for queries involving the grouping functionsmin()
andmax()
, and prevents the query plan from being changed by theALTER TABLE
statement. (The more stable query plan might or might not use a Loose Index Scan.) (Bug #14200010)InnoDB: When the primary key of a table includes a column prefix, and a full-text index is defined on the table, a full-text search resulted in an unnecessary warning being written to the error log. This fix suppresses the unnecessary warning. (Bug #16169411)
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InnoDB: In online DDL operations, a
DROP FOREIGN KEY
clause was not allowed in anALTER TABLE
statement that also performed any of the following:Adding or dropping a column.
Adding or dropping a primary key index.
Making a column
NULL
orNOT NULL
.Reordering columns.
Changing the
ROW_FORMAT
orKEY_BLOCK_SIZE
properties.
(Bug #16095573, Bug #68019)
InnoDB: Some Valgrind warnings were issued during shutdown, while cleaning up a background thread that handles optimization of tables containing
FULLTEXT
indexes. (Bug #15994393)InnoDB: During an online DDL operation, changing a column from nullable to
NOT NULL
could succeed or fail differently depending on whether theALTER TABLE
statement usedALGORITHM=INPLACE
orALGORITHM=COPY
. An operation withALGORITHM=COPY
would succeed even if the column containedNULL
values, while an operation withALGORITHM=INPLACE
failed because of the possibility that the column containedNULL
values. Now, making a columnNOT NULL
in combination with theALGORITHM=INPLACE
clause is allowed, but only if thesql_mode
configuration option includes theSTRICT_TRANS_TABLES
orSTRICT_ALL_TABLES
setting. If theALGORITHM
clause is not specified with theALTER TABLE
statement, the online DDL operation will useALGORITHM=INPLACE
if possible, orALGORITHM=COPY
if not. (Bug #15961327)-
InnoDB: Under certain circumstances, an
InnoDB
table was reported as corrupted after import usingALTER TABLE ... IMPORT TABLESPACE
. The problem was accompanied by one of these messages:Warning : InnoDB: The B-tree of index "PRIMARY" is corrupted. error : Corrupt
or:
Warning : InnoDB: The B-tree of index "GEN_CLUST_INDEX" is corrupted. error : Corrupt
This issue occurred intermittently, and primarily affected large tables. The
REPAIR TABLE
statement would fix the problem reported by the error message. (Bug #15960850, Bug #67807) -
InnoDB: Names of indexes being created by an online DDL operation were being displayed incorrectly in
INFORMATION_SCHEMA
tables while the operation was in progress. This fix ensures the table names have the leading0xff
byte stripped off forINFORMATION_SCHEMA
queries. This change affects the columns:innodb_buffer_page.index_name
innodb_buffer_page_lru.index_name
innodb_cmp_per_index.index_name
innodb_cmp_per_index_reset.index_name
innodb_locks.lock_index
innodb_sys_indexes.name
(Bug #15946256)
InnoDB:
ALTER TABLE
statements using the online DDL feature could cause Valgrind warnings. (Bug #15933178)InnoDB: If an online DDL operation to add a unique index failed, because duplicate items were created by concurrent DML during the online DDL operation, the
ALTER TABLE
operation failed with the wrong error type. It returnedER_INDEX_CORRUPT
; now it returns the new error codeER_DUP_UNKNOWN_IN_INDEX
. (It does not returnER_DUP_KEY
, because the duplicate key value is not available to be reported when this condition occurs.) (Bug #15920713)InnoDB: During an online DDL operation to add a unique index, DML operations that created duplicate values could fail with an
ER_DUP_KEY
error even though the index had not been made visible yet. (There was a brief time window when this condition could occur.) The fix causes the index creation operation to fail instead, if the index would be invalid because of duplicate entries produced by concurrent DML. (Bug #15920445)InnoDB: Specifying an
innodb_log_file_size
value of 4GB or larger was not possible on 64-bit Windows systems. This issue only affected debug builds. (Bug #15882860)InnoDB: If the server crashed near the end of an online DDL
ALTER TABLE
statement, a subsequentCHECK TABLE
statement using theEXTENDED
clause could cause a serious error. (Bug #15878013)InnoDB: Creating an index on a
CHAR
column could fail for a table with a character set with varying length, such asutf8
, if the table was created with theROW_FORMAT=REDUNDANT
clause. (Bug #15874001)InnoDB: This fix ensures that in case of a serious unhandled error during an
ALTER TABLE
operation that copies the original table, any data that could be needed for data recovery is preserved, in tables using names of the form#sql-ib-
ortable_id
#mysql50##sql-ib-
. (Bug #15866623)table_id
InnoDB: The status variable
Innodb_buffer_pool_read_ahead_evicted
could show an inaccurate value, higher than expected, because some pages in the buffer pool were incorrectly considered as being brought in by read-ahead requests. (Bug #15859402, Bug #67476)-
InnoDB: An online DDL operation to add a primary key to a table could encounter a serious error if the table also had an index on a column prefix of a
BLOB
column.This fix suspends the background purge operation while a table is being rebuilt by an
ALTER TABLE
statement, if any rows containing off-page columns would be removed. Currently, to avoid excessive space usage during the online DDL operation, avoid these types of concurrent DML operations until theALTER TABLE
is finished:(Bug #14827736)
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InnoDB: The server could halt with an assertion error while creating an index:
InnoDB: Assertion failure in thread thread_num in file row0merge.cc line 465
This issue affected tables with a combination of
ROW_FORMAT=REDUNDANT
off-page columns, and an index on a column prefix. (Bug #14753402) -
InnoDB: The server could halt with an assertion error when creating an index on a column prefix for a column using a multibyte character set:
InnoDB: Assertion failure in thread thread_num in file row0merge.cc line 465 InnoDB: Failing assertion: len == ifield-<fixed_len
(Bug #14753402)
InnoDB: A regression introduced by the fix for Bug#14100254 would result in a “!BPAGE->FILE_PAGE_WAS_FREED” assertion. (Bug #14676249)
InnoDB:
INFORMATION_SCHEMA
tables withInnoDB
metadata, such asinnodb_sys_tablestats
, displayed nonalphanumeric characters in the names of tables using an encoded format, for example with@0024
instead of$
. (Bug #14550145)InnoDB: If the value of
innodb_force_recovery
was less than 6, opening a corrupted table might loop forever if a corrupted page was read when calculating statistics for the table. Information about the corrupted page was written repeatedly to the error log, possibly causing a disk space issue. The fix causes the server to halt after a fixed number of failed attempts to read the page. To troubleshoot such a corruption issue, setinnodb_force_recovery=6
and restart. (Bug #14147491, Bug #65469)InnoDB: With a large value for
innodb_buffer_pool_size
, andinnodb_buffer_pool_instances
set greater than 1, pages were being incorrectly evicted from the buffer pool. (Bug #14125092)InnoDB: Corruption of the
innodb_ft_user_stopword_table
table could cause a server exit. (Bug #67960, Bug #16038656)-
Partitioning: Partition pruning is now enabled for tables using a storage engine that provides automatic partitioning, such as the
NDB
storage engine, but which are explicitly partitioned. Previously, pruning was disabled for all tables using such a storage engine, whether or not the tables had explicitly defined partitions.In addition, as part of this fix, explicit partition selection is now disabled for tables using a storage engine (such as
NDB
) that provides automatic partitioning. (Bug #14827952)References: See also: Bug #14672885.
Replication: When using GTID-based replication, and whenever a transaction was executed on the master but was not sent to the slave because the slave already had a transaction with that ID, semisynchrononous replication timed out. One case in which this could happen was during a failover operation where the new master started behind the new slave. (Bug #15985893)
Replication: An unnecessary flush to disk performed after every transaction when using
FILE
as the replication info repository type could degrade performance. Now this is done only when both data and relay log info is stored in (transactional) tables. (Bug #15980626)Replication: Issuing
START SLAVE UNTIL SQL_BEFORE_GTIDS =
, wheregtid_set
gtid_set
covered a large number (tens or hundreds of millions) of transactions, could cause the server to hang. (Bug #15968413)-
Replication: When a slave was started using
--skip-innodb
and replication info file repositories (FILE
being the default for both themaster_info_repository
andrelay_log_info_repository
system variables), replication was incorrectly stopped. However, if the slave is using file repositories and not currently migrating between info repositories, replication should be able to work without issues. Now the server ignores errors raised when trying to open table info repositories in such conditions.In addition, binary log initialization was not performed correctly when starting the slave with
--skip-innodb
, which caused the--log-bin option
to be ignored. (Bug #15956714, Bug #67798, Bug #15971607) -
Replication: When temporary and persistent tables, or temporary tables using different storage engines, are dropped in a single statement, this statement is actually written as two statements to the binary log, each represented by its own log event. When
gtid_mode
isON
, each DDL event must have a GTID; however, in such cases, the statement dropping the temporary table was uncommitted, which meant that it was not given its own GTID.Now, when a DDL statement dropping a temporary table and a table that is persistent, or that uses a different storage engine, is separated in the manner just described, and the resulting logged statement affecting only the temporary table does not implicitly commit, a commit is forced so that the corresponding log event has own unique GTID. (Bug #15947962)
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Replication: Semisynchronous replication did not work correctly with GTIDs enabled. (Bug #15927032)
References: See also: Bug #14737388.
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Replication: When used on a binary log that had been written by a GTID-enabled server, mysqlbinlog did not correctly handle transactions left unclosed by the omission of statements that were ignored when the
--database
option was employed.Now, whenever mysqlbinlog
--database
reads a GTID log event, it checks to see whether there is an unclosed transaction, and if so, issues a commit. (Bug #15912728) Replication: When GTIDs were enabled, the automatic dropping of a temporary table when a client disconnected did not always generate a GTID. Now each logged
DROP TABLE
statement, including any generated by the server, is guaranteed to have its own GTID. (Bug #15907504)Replication: When a binary log is replayed on a server (for example, by executing a command like mysqlbinlog
binlog.000001
|
mysql), it sets a pseudo-slave mode on the client connection used, so that the server can read binary log and apply binary log events correctly. However, the pseudo-slave mode was not disabled after the binary log dump was read, which caused unexpected filtering rules to be applied to SQL statements subsequently executed on the same connection. (Bug #15891524)Replication: After dropping a column from the slave's version of a table, then altering the same column of this table on the master (so that a type conversion would have been required had the column not been droppped on the slave), inserts into this table caused replication to fail. (Bug #15888454)
Replication: Use of
sql_slave_skip_counter
is not compatible with GTID-based replication. Setting this variable to a nonzero value is now disallowed whenever--gtid-mode = ON
, and attempting to do so fails with an error. (Bug #15833516)Replication: During mysqld shutdown, global GTID variables were released before it was made certain that all plugins had stopped using them. (Bug #14798275)
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Replication:
MASTER_POS_WAIT()
could hang or return -1 due to invalid updates by the slave SQL thread when transactions were skipped by the GTID protocol. (Bug #14775893)References: See also: Bug #15927032.
Replication: Trying to execute a Stop event on a multithreaded slave could cause unwanted updates to the relay log, leading the slave to lose synchronization with the master. (Bug #14737388)
Replication: Names of databases in binary log query log events were not properly checked for length. (Bug #14636219)
Replication: Issuing
START SLAVE
concurrently with settingsql_slave_skip_counter
orslave_net_timeout
could cause a deadlock. (Bug #14236151)Replication: When using statement-based replication, and where the master and the slave used table schemas having different
AUTO_INCREMENT
columns, inserts generatingAUTO_INCREMENT
values logged for a given table on the master could be applied to the wrong table on the slave. (Bug #12669186)Replication: Repeated execution of
CHANGE MASTER TO
statements using invalidMASTER_LOG_POS
values could lead to errors and possibly a crash on the slave. Now in such cases, the statement fails with a clear error message. (Bug #11764602, Bug #57454)Microsoft Windows: Dynamic file names (with colons) are no longer allowed. Static file names using the Alternate Data Stream (ADS) NTFS functionality of Microsoft Windows may continue to be used. (Bug #11761752)
Oracle RPM packages were unusable by
yum
due to issues with theobsoletes
line in the.spec
file causing yum to interpret the package as obsoleting itself. (Bug #16298542)During client connection processing, the server now performs password-expiration checking after SSL checks. (Bug #16103348)
The plugin logging routine mishandled its argument, resulting in undefined behavior. (Bug #16002890)
A buffer-handling problem in yaSSL was fixed. (Bug #15965288)
Within a stored procedure, executing a multiple-table
DELETE
statement that used a very long table alias could cause the server to exit. (Bug #15954896)Metadata locking and table definition cache routines did not always check length of names passed to them. (Bug #15954872)
In the absence of a
FULLTEXT
index on anInnoDB
table, a full-text query withCOUNT(*)
could raise an assertion. (Bug #15950531)-
In certain rare cases, a query using
UpdateXML()
could cause the server to crash. (Bug #15948580)References: See also: Bug #13007062.
Very long table aliases in queries could cause the server to exit. (Bug #15948123)
An online DDL operation that dropped an index could proceed despite not having sufficient locks on the table. This issue could cause a serious error, although the error was only observed in debug builds. (Bug #15936065)
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A comment added to mysqldump output for the
--set-gtid-purged
option was malformed and caused a syntax error when the dump file was reloaded. (Bug #15922502)References: See also: Bug #14832472.
Contention in the thread pool during kill processing could lead to a Valgrind panic. (Bug #15921866)
Several OpenSSL-related memory leaks were fixed. (Bug #15921729)
The
ALTER TABLE
statement can now use theLOCK=NONE
clause, allowing online DDL with concurrent DML, for child tables containing foreign key constraints. (Bug #15912214)Very long database names in queries could cause the server to exit. (Bug #15912213, Bug #16900358)
AES_DECRYPT()
andAES_ENCRYPT()
had memory leaks when MySQL was compiled using OpenSSL. (Bug #15909183)Several OpenSSL-related Valgrind warnings were corrected. (Bug #15908967)
An
ALTER TABLE
with theADD PRIMARY KEY
orADD UNIQUE INDEX
clause could encounter a serious error if the columns for the primary key or unique index contained duplicate entries. This error occurred intermittently, depending on how the rows were physically distributed across index blocks. (Bug #15908291)Rows_log_event
allocated one too few bytes for the row buffer. (Bug #15890178)The Performance Schema normally ignores temporary table events. User-defined temporary tables are truncated by being re-created, but the Performance Schema did not recognize re-created temporary tables as being temporary and raised an assertion. (Bug #15884836)
Several code issues identified by Fortify were corrected. (Bug #15884324)
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In debug builds, the server could not start on 64-bit Windows systems when a value of 16 GB or higher was specified for
innodb_buffer_pool_size
. Non-debug builds would likely have subtler issues, such as memory being allocated for the buffer pool but not used, or read requests overlooking pages already cached in the buffer pool.On 32-bit Windows systems, the value of
innodb_buffer_pool_instances
is increased if necessary so that no buffer pool instance is larger than 1.3 GB, due to system limitations on memory allocation. This automatic adjustment needed for 32-bit Windows systems was incorrectly applied to 64-bit systems also; for systems with 16 GB or larger buffer pools, the adjusted value ofinnodb_buffer_pool_instances
would exceed the upper limit of 64, causing an assertion error in debug builds. (Bug #15883071) A heavy workload of online DDL and concurrent DML on a table on a master server could cause errors as the changes were replicated to slave servers. For example, processing a
DROP COLUMN
operation at the same time as queries referring to the dropped column could cause errors on slave servers if the statements finished in a different order than on the master. (Bug #15878880)Complex
IN
subqueries could cause the server to exit. (Bug #15877738)In some cases, a cost value was printed to Optimizer Trace output without being initialized, resulting in incorrect output. (Bug #15877453)
Some queries, if used as prepared statements, caused the server to exit if an error occurred. (Bug #15877062)
If an error occurred during the final phase of an online DDL operation, some cached metadata about the table might not be restored to its original state. This issue typically affected operations that renamed a column, and also dropped and re-created an index on that column, in the same
ALTER TABLE
statement. This issue did not affect operations that reorganize the clustered index of the table, such as adding a new primary key. (Bug #15866734)-
The optimizer's cost-based choice between
IN -> EXISTS
subquery transformation and subquery materialization was sometimes incorrect if theIN
predicate wasOR
-ed with some other predicate. (Bug #15866339)References: See also: Bug #13111584.
The
session_connect_attrs
Performance Schema table displayed extraneous information. (Bug #15864703)For the LooseScan semijoin strategy, the optimizer could rely on an uninitialized variable. (Bug #15849654)
It was possible to expire the password for an account even if the account is authenticated by an authentication plugin that does not support password expiration. (Bug #15849009)
If Loose Index Scan was used on a query with descending order, the result set contained
NULL
values instead of the correct values. (Bug #15848665)For debug builds, an assertion could be raised when: 1) A view was based on a
MEMORY
table; 2) The table was altered to drop some column in use by the view; 3) ASELECT
was done on the view with binary logging disabled. (Bug #15847447)-
If the server shut down unexpectedly, the presence of an
InnoDB
table with 1018 columns (very close to the upper limit of 1020 columns) could cause an assertion error during server restart:InnoDB: Failing assertion: table->n_def == table->n_cols - 3
(Bug #15834685)
-
Subqueries with
COUNT(DISTINCT ...))
could cause the server to exit. (Bug #15832620)References: See also: Bug #11750963.
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Setting the
validate_password_length
system variable did not take into account that the minimum value is a function of several other related system variables. Now the server will not set the value less than the value of this expression:validate_password_number_count + validate_password_special_char_count + (2 * validate_password_mixed_case_count)
(Bug #14850601)
GRANT ... IDENTIFIED BY
could fail to flush the privileges. (Bug #14849959)When the server reads the
mysql.user
table, it now checks for invalid native and old-native password hashes and ignores accounts with invalid hashes. (Bug #14845445)The
validate_password
plugin did not check certain passwords. (Bug #14843970)mysqladmin did not properly process commands for users with expired passwords. (Bug #14833621)
MySQL could encounter an error during shutdown on Windows XP or earlier systems. This issue did not affect systems running Windows Vista or higher, which use atomic condition variables to represent Windows Events. (Bug #14822849)
An issue with locking order for the system tables and the InnoDB data dictionary could lead to an internal deadlock within MySQL. (Bug #14805484)
Temporary table creation during execution of
INFORMATION_SCHEMA
queries could result in Valgrind warnings. (Bug #14801497)When used with an XPath expression that contained the output of a stored function,
ExtractValue()
failed with the error Only constant XPATH queries are supported. (Bug #14798445, Bug #67313)-
The server could halt with an assertion error due to a recently added error code:
InnoDB: unknown error code 1502 InnoDB: Assertion failure in thread thread_num in file row0mysql.cc line 683 mysqld got signal 6 ;
Now, the server returns the error code
DB_DICT_CHANGED
to the client in this case. (Bug #14764015) The clause
ALGORITHM=INPLACE
clause in anALTER TABLE
statement for a partitioned table could lead to consistency issues if a crash occurred while changes were applied to some of the underlying tables but not all. This fix prohibits theALGORITHM=INPLACE
clause for DDL operations on partitioned tables. (Bug #14760210)The
sha256_password
authentication plugin requires that the client connect either using SSL or have RSA enabled. When neither condition was met, an uninformative error message was produced. Now the error message is more informative. (Bug #14751925)Queries that used grouping failed when executed using a cursor if the optimizer processed the grouping using a temporary table. (Bug #14740889)
XA START
had a race condition that could cause a server crash. (Bug #14729757)The server could exit when the
MyISAM
storage engine (rather thanMEMORY
) was used to materialize a derived table. (Bug #14728469)The server now logs warnings at startup if the file specified for the
validate_password_dictionary_file
system variable violates constraints on valid password file contents. (Bug #14588148)Calculations involving self-intersecting polygons caused an assertion to be raised. (Bug #14503584)
At startup, some options and system variables variables could be set to 1 or 0, but not
ON
orOFF
. MySQL programs now acceptON
andOFF
on the command line and in option files. (Bug #14494893)Output generated with mysqldump --routines could produce syntax errors when reloaded. (Bug #14463669)
If
ALTER TABLE
was killed, the server could reportER_QUERY_INTERRUPTED
even if the alterations had been made successfully. This is misleading to the user. Also, the statement would not be written to the binary log, leading to incorrect replication (Bug #14382643)With the
ONLY_FULL_GROUP_BY
SQL mode enabled, executing a stored function twice that contains an SQL query that is not valid with that mode enabled caused the server to exit. (Bug #13996639)-
Preloading of client plugins specified with the
LIBMYSQL_PLUGINS
environment variable could fail unless the plugins were located in the hardwired default plugin directory. The C API now checks during plugin preloading for aLIBMYSQL_PLUGIN_DIR
environment variable which can be set to the path name of the directory in which to look for client plugins.In addition, for explicit client plugin loading, the
mysql_load_plugin()
andmysql_load_plugin_v()
C API functions have been modified to use theLIBMYSQL_PLUGIN_DIR
value if it exists and the--plugin-dir
option was not given. If--plugin-dir
is given,mysql_load_plugin()
andmysql_load_plugin_v()
ignoreLIBMYSQL_PLUGIN_DIR
. (Bug #13994567, Bug #18110355) The parser failed to return an error for some invalid
UNION
constructs. (Bug #13992148)Due to a thread race condition, the server could exit while attempting to read the Performance Schema
threads.PROCESSLIST_INFO
column. (Bug #68127, Bug #16196158)Some messages written by the server to the error log referred to the deprecated
--log-slow-queries
option rather than the--slow-query-log
option. Similarly, the server referred to the deprecated--log
option rather than the--general-log-file
and--log-output
options. (Bug #67892, Bug #15996571)Autosizing of Performance Schema parameters could result in settings that caused excessive CPU use. (Bug #67736, Bug #15927744)
For single-table
DELETE
orUPDATE
statements,EXPLAIN
displayed atype
value ofALL
(full-table scan access method) even if the optimizer chose to scan the table by an index access method. Now thetype
value is displayed asindex
. (Bug #67637, Bug #15892875)The optimizer could choose an
IN
-to-EXISTS
transformation for subquery execution in some cases when subquery materialization would be cheaper. (Bug #67511, Bug #15848521)It is not permitted to use
CREATE TABLE
to create anNDB
table with user-defined partitioning and a foreign key. However, it was possible to create anNDB
table with a foreign key, then add partitioning to it usingALTER TABLE
, thus creating a table which was impossible to back up or restore using mysqldump. Now the prohibition is enforced consistently. (Bug #67492, Bug #15844519)The optimizer sometimes chose a nonoptimimal range scan strategy when a query included a
LIMIT
clause. (Bug #67432, Bug #15829358)Attempting to perform an in-place upgrade from MySQL 5.1 to 5.6 causes the server to exit due to a mismatch between the privilege structures in the two series. (This is not a supported operation, but the server should not exit ungracefully.) (Bug #67319, Bug #14826854)
mysqldump could fail to dump all tables in the
mysql
database. (Bug #67261, Bug #14771252)Full-text searches in
InnoDB
tables could return incorrect results. (Bug #67257, Bug #14771282)The Performance Schema normally ignores temporary table events, but sometimes failed to properly identify a table as temporary and consequently recorded events for the table. (Bug #67098, Bug #14756887)
The mysql client could mishandle the
delimiter
command if it occurred on a line during whichmysql
was looking for the end of a quoted string. (Bug #64135, Bug #13639125)DECIMAL
multiplication operations could produce significant inaccuracy. (Bug #45860, Bug #11754279)