Incompatible Change: The parser accepted statements that contained /* ... */ that were not properly closed with */, such as SELECT 1 /* + 2. Statements that contain unclosed /*-comments now are rejected with a syntax error.

This fix has the potential to cause incompatibilities. Because of Bug#26302, which caused the trailing */ to be truncated from comments in views, stored routines, triggers, and events, it is possible that objects of those types may have been stored with definitions that now will be rejected as syntactically invalid. Such objects should be dropped and re-created so that their definitions do not contain truncated comments. If a stored object definition contains only a single statement (does not use a BEGIN ... END block) and contains a comment within the statement, the comment should be moved to follow the statement or the object should be rewritten to use a BEGIN ... END block. For example, this statement:

CREATE PROCEDURE p() SELECT 1 /* my comment */ ;

Can be rewritten in either of these ways:

CREATE PROCEDURE p() SELECT 1; /* my comment */
CREATE PROCEDURE p() BEGIN SELECT 1 /* my comment */ ; END;

(Bug#28779)

MySQL Cluster: Mapping of NDB error codes to MySQL storage engine error codes has been improved. (Bug#28423)

MySQL Cluster: auto_increment_increment and auto_increment_offset are now supported for NDB tables. (Bug#26342)

MySQL Cluster: The output from the cluster management client showing the progress of data node starts has been improved. (Bug#23354)

Replication: The sql_mode, foreign_key_checks, unique_checks, character set/collations, and sql_auto_is_null session variables are written to the binary log and honored during replication. See Section 5.2.3, “The Binary Log”.

Server parser performance was improved for expression parsing by lowering the number of state transitions and reductions needed. (Bug#30625)

Server parser performance was improved for boolean expressions. (Bug#30237)

If a MyISAM table is created with no DATA DIRECTORY option, the .MYD file is created in the database directory. By default, if MyISAM finds an existing .MYD file in this case, it overwrites it. The same applies to .MYI files for tables created with no INDEX DIRECTORY option. To suppress this behavior, start the server with the new --keep_files_on_create option, in which case MyISAM will not overwrite existing files and returns an error instead. (Bug#29325)

MySQL source distributions are now available in Zip format. (Bug#27742)

If a MERGE table cannot be opened or used because of a problem with an underlying table, CHECK TABLE now displays information about which table caused the problem. (Bug#26976)

The EXAMPLE storage engine is now enabled by default.

Security Fix: Using RENAME TABLE against a table with explicit DATA DIRECTORY and INDEX DIRECTORY options can be used to overwrite system table information by replacing the symbolic link points. the file to which the symlink points.

MySQL will now return an error when the file to which the symlink points already exists. (Bug#32111, CVE-2007-5969)

Incompatible Change: The file mysqld.exe was mistakenly included in binary distributions between MySQL 5.0.42 and 5.0.48. You should use mysqld-nt.exe. (Bug#32197)

Incompatible Change: Multiple-table DELETE statements containing ambiguous aliases could have unintended side effects such as deleting rows from the wrong table. Example:

DELETE FROM t1 AS a2 USING t1 AS a1 INNER JOIN t2 AS a2;

This bug fix enables alias declarations to be declared only in the table_references part. Elsewhere in the statement, alias references are allowed but not alias declarations. (Bug#30234)

See also Bug#27525.

Incompatible Change: Failure to consider collation when comparing space characters could result in incorrect index entry order, leading to incorrect comparisons, inability to find some index values, misordered index entries, misordered ORDER BY results, or tables that CHECK TABLE reports as having corrupt indexes.

As a result of this bug fix, indexes must be rebuilt for columns that use any of these character sets: eucjpms, euc_kr, gb2312, latin7, macce, ujis. See Section 2.18.3, “Checking Whether Tables or Indexes Must Be Rebuilt”. (Bug#29461)

MySQL Cluster: Packaging: Some commercial MySQL Cluster RPM packages included support for the InnoDB storage engine. (InnoDB is not part of the standard commercial MySQL Cluster offering.) (Bug#31989)

MySQL Cluster: Attempting to restore a backup made on a cluster host using one endian to a machine using the other endian could cause the cluster to fail. (Bug#29674)

MySQL Cluster: When restarting a data node, queries could hang during that node's start phase 5, and continue only after the node had entered phase 6. (Bug#29364)

MySQL Cluster: Replica redo logs were inconsistently handled during a system restart. (Bug#29354)

MySQL Cluster: Reads on BLOB columns were not locked when they needed to be to guarantee consistency. (Bug#29102)

See also Bug#31482.

MySQL Cluster: A query using joins between several large tables and requiring unique index lookups failed to complete, eventually returning Uknown Error after a very long period of time. This occurred due to inadequate handling of instances where the Transaction Coordinator ran out of TransactionBufferMemory, when the cluster should have returned NDB error code 4012 (Request ndbd time-out). (Bug#28804)

MySQL Cluster: The description of the --print option provided in the output from ndb_restore --help was incorrect. (Bug#27683)

MySQL Cluster: The management client's response to START BACKUP WAIT COMPLETED did not include the backup ID. (Bug#27640)

MySQL Cluster: An invalid subselect on an NDB table could cause mysqld to crash. (Bug#27494)

MySQL Cluster: An attempt to perform a SELECT ... FROM INFORMATION_SCHEMA.TABLES whose result included information about NDB tables for which the user had no privileges crashed the MySQL Server on which the query was performed. (Bug#26793)

MySQL Cluster: Warnings and errors generated by ndb_config --config-file=file were sent to stdout, rather than to stderr. (Bug#25941)

MySQL Cluster: Large file support did not work in AIX server binaries. (Bug#10776)

Replication: The thread ID was not reset properly after execution of mysql_change_user(), which could cause replication failure when replicating temporary tables. (Bug#29734)

Replication: Operations that used the time zone replicated the time zone only for successful operations, but did not replicate the time zone for errors that need to know it. (Bug#29536)

Replication: INSERT DELAYED statements on a master server are replicated as non-DELAYED inserts on slaves (which is normal, to preserve serialization), but the inserts on the slave did not use concurrent inserts. Now INSERT DELAYED on a slave is converted to a concurrent insert when possible, and to a normal insert otherwise. (Bug#29152)

Replication: DROP USER statements that named multiple users, only some of which could be dropped, were replicated incorrectly. (Bug#29030)

Replication: An error that happened inside INSERT, UPDATE, or DELETE statements performed from within a stored function or trigger could cause inconsistency between master and slave servers. (Bug#27417)

Replication: Slave servers could incorrectly interpret an out-of-memory error from the master and reconnect using the wrong binary log position. (Bug#24192)

When a TIMESTAMP with a nonzero time part was converted to a DATE value, no warning was generated. This caused index lookups to assume that this is a valid conversion and was returning rows that match a comparison between a TIMESTAMP value and a DATE keypart. Now a warning is generated so that TIMESTAMP with a nonzero time part will not match DATE values. (Bug#31221)

A server crash could occur when a non-DETERMINISTIC stored function was used in a GROUP BY clause. (Bug#31035)

For an InnoDB table if a SELECT was ordered by the primary key and also had a WHERE field = value clause on a different field that was indexed, a DESC order instruction would be ignored. (Bug#31001)

A failed HANDLER ... READ operation could leave the table in a locked state. (Bug#30632)

The optimization that uses a unique index to remove GROUP BY did not ensure that the index was actually used, thus violating the ORDER BY that is implied by GROUP BY. (Bug#30596)

SHOW STATUS LIKE 'Ssl_cipher_list' from a MySQL client connected via SSL returned an empty string rather than a list of available ciphers. (Bug#30593)

Memory corruption occurred for some queries with a top-level OR operation in the WHERE condition if they contained equality predicates and other sargable predicates in disjunctive parts of the condition. (Bug#30396)

Issuing a DELETE statement having both an ORDER BY clause and a LIMIT clause could cause mysqld to crash. (Bug#30385)

The Last_query_cost status variable value can be computed accurately only for simple “flat” queries, not complex queries such as those with subqueries or UNION. However, the value was not consistently being set to 0 for complex queries. (Bug#30377)

Queries that had a GROUP BY clause and selected COUNT(DISTINCT bit_column) returned incorrect results. (Bug#30324)

The server created temporary tables for filesort operations in the working directory, not in the directory specified by the tmpdir system variable. (Bug#30287)

The query cache does not support retrieval of statements for which column level access control applies, but the server was still caching such statements, thus wasting memory. (Bug#30269)

Using DISTINCT or GROUP BY on a BIT column in a SELECT statement caused the column to be cast internally as an integer, with incorrect results being returned from the query. (Bug#30245)

GROUP BY on BIT columns produced incorrect results. (Bug#30219)

Using KILL QUERY or KILL CONNECTION to kill a SELECT statement caused a server crash if the query cache was enabled. (Bug#30201)

Prepared statements containing CONNECTION_ID() could be written improperly to the binary log. (Bug#30200)

When a thread executing a DROP TABLE statement was killed, the table name locks that had been acquired were not released. (Bug#30193)

Short-format mysql commands embedded within /*! ... */ comments were parsed incorrectly by mysql, which discarded the rest of the comment including the terminating */ characters. The result was a malformed (unclosed) comment. Now mysql does not discard the */ characters. (Bug#30164)

When mysqldump wrote DROP DATABASE statements within version-specific comments, it included the terminating semicolon in the wrong place, causing following statements to fail when the dump file was reloaded. (Bug#30126)

Use of local variables with non-ASCII names in stored procedures crashed the server. (Bug#30120)

On Windows, client libraries lacked symbols required for linking. (Bug#30118)

--myisam-recover='' (empty option value) did not disable MyISAM recovery. (Bug#30088)

The IS_UPDATABLE column in the INFORMATION_SCHEMA.VIEWS table was not always set correctly. (Bug#30020)

Statements within stored procedures ignored the value of the low_priority_updates system variable. (Bug#29963)

See also Bug#26162.

For MyISAM tables on Windows, INSERT, DELETE, or UPDATE followed by ALTER TABLE within LOCK TABLES could cause table corruption. (Bug#29957)

With auto-reconnect enabled, row fetching for a prepared statement could crash after reconnect occurred because loss of the statement handler was not accounted for. (Bug#29948)

LOCK TABLES did not pre-lock tables used in triggers of the locked tables. Unexpected locking behavior and statement failures similar to failed: 1100: Table 'xx' was not locked with LOCK TABLES could result. (Bug#29929)

INSERT ... VALUES(CONNECTION_ID(), ...) statements were written to the binary log in such a way that they could not be properly restored. (Bug#29928)

Adding DISTINCT could cause incorrect rows to appear in a query result. (Bug#29911)

Using the DATE() function in a WHERE clause did not return any records after encountering NULL. However, using TRIM() or CAST() produced the correct results. (Bug#29898)

Very long prepared statements in stored procedures could cause a server crash. (Bug#29856)

If query execution involved a temporary table, GROUP_CONCAT() could return a result with an incorrect character set. (Bug#29850)

If one thread was performing concurrent inserts, other threads reading from the same table using equality key searches could see the index values for new rows before the data values had been written, leading to reports of table corruption. (Bug#29838)

Repeatedly accessing a view in a stored procedure (for example, in a loop) caused a small amount of memory to be allocated per access. Although this memory is deallocated on disconnect, it could be a problem for a long running stored procedures that make repeated access of views. (Bug#29834)

mysqldump produced output that incorrectly discarded the NO_AUTO_VALUE_ON_ZERO value of the sql_mode variable after dumping triggers. (Bug#29788)

An assertion failure occurred within yaSSL for very long keys. (Bug#29784)

For MEMORY tables, the index_merge union access method could return incorrect results. (Bug#29740)

Comparison of TIME values using the BETWEEN operator led to string comparison, producing incorrect results in some cases. Now the values are compared as integers. (Bug#29739)

For a table with a DATE column date_col such that selecting rows with WHERE date_col = 'date_val 00:00:00' yielded a nonempty result, adding GROUP BY date_col caused the result to be empty. (Bug#29729)

In some cases, INSERT INTO ... SELECT ... GROUP BY could insert rows even if the SELECT by itself produced an empty result. (Bug#29717)

For the embedded server, the mysql_stmt_store_result() C API function caused a memory leak for empty result sets. (Bug#29687)

EXPLAIN produced Impossible where for statements of the form SELECT ... FROM t WHERE c=0, where c was an ENUM column defined as a primary key. (Bug#29661)

On Windows, ALTER TABLE hung if records were locked in share mode by a long-running transaction. (Bug#29644)

A left join between two views could produce incorrect results. (Bug#29604)

Certain statements with unions, subqueries, and joins could result in huge memory consumption. (Bug#29582)

Clients using SSL could hang the server. (Bug#29579)

A slave running with --log-slave-updates would fail to write INSERT DELAY IGNORE statements to its binary log, resulting in different binary log contents on the master and slave. (Bug#29571)

An incorrect result was returned when comparing string values that were converted to TIME values with CAST(). (Bug#29555)

gcov coverage-testing information was not written if the server crashed. (Bug#29543)

In the ascii character set, conversion of DEL (0x7F) to Unicode incorrectly resulted in QUESTION MARK (0x3F) rather than DEL. (Bug#29499)

A field packet with NULL fields caused a libmysqlclient crash. (Bug#29494)

When using a combination of HANDLER... READ and DELETE on a table, MySQL continued to open new copies of the table every time, leading to an exhaustion of file descriptors. (Bug#29474)

This regression was introduced by Bug#21587.

On Windows, the mysql client died if the user entered a statement and Return after entering Control-C. (Bug#29469)

Corrupt data resulted from use of SELECT ... INTO OUTFILE 'file_name' FIELDS ENCLOSED BY 'c', where c is a digit or minus sign, followed by LOAD DATA INFILE 'file_name' FIELDS ENCLOSED BY 'c'. (Bug#29442)

Killing an INSERT DELAYED thread caused a server crash. (Bug#29431)

Use of SHOW BINLOG EVENTS for a nonexistent log file followed by PURGE BINARY LOGS caused a server crash. (Bug#29420)

Assertion failure could occur for grouping queries that employed DECIMAL user variables with assignments to them. (Bug#29417)

For CAST(expr AS DECIMAL(M,D)), the limits of 65 and 30 on the precision (M) and scale (D) were not enforced. (Bug#29415)

If a view used a function in its SELECT statement, the columns from the view were not inserted into the INFORMATION_SCHEMA.COLUMNS table. (Bug#29408)

Results for a select query that aliases the column names against a view could duplicate one column while omitting another. This bug could occur for a query over a multiple-table view that includes an ORDER BY clause in its definition. (Bug#29392)

mysqldump created a stray file when a given a too-long file name argument. (Bug#29361)

The special “zero” ENUM value was coerced to the normal empty string ENUM value during a column-to-column copy. This affected CREATE ... SELECT statements and SELECT statements with aggregate functions on ENUM columns in the GROUP BY clause. (Bug#29360)

Optimization of queries with DETERMINISTIC stored functions in the WHERE clause was ineffective: A sequential scan was always used. (Bug#29338)

MyISAM corruption could occur with the cp932_japanese_ci collation for the cp932 character set due to incorrect comparison for trailing space. (Bug#29333)

The mysql_list_fields() C API function incorrectly set MYSQL_FIELD::decimals for some view columns. (Bug#29306)

FULLTEXT indexes could be corrupted by certain gbk characters. (Bug#29299)

SELECT ... INTO OUTFILE followed by LOAD DATA could result in garbled characters when the FIELDS ENCLOSED BY clause named a delimiter of '0', 'b', 'n', 'r', 't', 'N', or 'Z' due to an interaction of character encoding and doubling for data values containing the enclosed-by character. (Bug#29294)

Sort order of the collation wasn't used when comparing trailing spaces. This could lead to incorrect comparison results, incorrectly created indexes, or incorrect result set order for queries that include an ORDER BY clause. (Bug#29261)

If an ENUM column contained '' as one of its members (represented with numeric value greater than 0), and the column contained error values (represented as 0 and displayed as ''), using ALTER TABLE to modify the column definition caused the 0 values to be given the numeric value of the nonzero '' member. (Bug#29251)

Calling mysql_options() after mysql_real_connect() could cause clients to crash. (Bug#29247)

CHECK TABLE for ARCHIVE tables could falsely report table corruption or cause a server crash. (Bug#29207)

Mixing binary and utf8 columns in a union caused field lengths to be calculated incorrectly, resulting in truncation. (Bug#29205)

AsText() could fail with a buffer overrun. (Bug#29166)

InnoDB refused to start on some versions of FreeBSD with LinuxThreads. This is fixed by enabling file locking on FreeBSD. (Bug#29155)

LOCK TABLES was not atomic when more than one InnoDB tables were locked. (Bug#29154)

A network structure was initialized incorrectly, leading to embedded server crashes. (Bug#29117)

An assertion failure occurred if a query contained a conjunctive predicate of the form view_column = constant in the WHERE clause and the GROUP BY clause contained a reference to a different view column. The fix also enables application of an optimization that was being skipped if a query contained a conjunctive predicate of the form view_column = constant in the WHERE clause and the GROUP BY clause contained a reference to the same view column. (Bug#29104)

A maximum of 4TB InnoDB free space was reported by SHOW TABLE STATUS, which is incorrect on systems with more than 4TB space. (Bug#29097)

If an INSERT INTO ... SELECT statement inserted into the same table that the SELECT retrieved from, and the SELECT included ORDER BY and LIMIT clauses, different data was inserted than the data produced by the SELECT executed by itself. (Bug#29095)

Queries that performed a lookup into a BINARY index containing key values ending with spaces caused an assertion failure for debug builds and incorrect results for nondebug builds. (Bug#29087)

The semantics of BIGINT depended on platform-specific characteristics. (Bug#29079)

A byte-order issue in writing a spatial index to disk caused bad index files on some systems. (Bug#29070)

If one of the queries in a UNION used the SQL_CACHE option and another query in the UNION contained a nondeterministic function, the result was still cached. For example, this query was incorrectly cached:

SELECT NOW() FROM t1 UNION SELECT SQL_CACHE 1 FROM t1;

(Bug#29053)

Creation of a legal stored procedure could fail if no default database had been selected. (Bug#29050)

REPLACE, INSERT IGNORE, and UPDATE IGNORE did not work for FEDERATED tables. (Bug#29019)

Inserting into InnoDB tables and executing RESET MASTER in multiple threads cause assertion failure in debug server binaries. (Bug#28983)

For a ucs2 column, GROUP_CONCAT() did not convert separators to the result character set before inserting them, producing a result containing a mixture of two different character sets. (Bug#28925)

Queries using UDFs or stored functions were cached. (Bug#28921)

For a join with GROUP BY and/or ORDER BY and a view reference in the FROM list, the query metadata erroneously showed empty table aliases and database names for the view columns. (Bug#28898)

Coercion of ASCII values to character sets that are a superset of ASCII sometimes was not done, resulting in illegal mix of collations errors. These cases now are resolved using repertoire, a new string expression attribute (see Section 9.1.8, “String Repertoire”). (Bug#28875)

Non-utf8 characters could get mangled when stored in CSV tables. (Bug#28862)

ALTER VIEW is not supported as a prepared statement but was not being rejected. ALTER VIEW is now prohibited as a prepared statement or when called within stored routines. (Bug#28846)

In strict SQL mode, errors silently stopped the SQL thread even for errors named using the --slave-skip-errors option. (Bug#28839)

Fast ALTER TABLE (that works without rebuilding the table) acquired duplicate locks in the storage engine. In MyISAM, if ALTER TABLE was issued under LOCK TABLE, it caused all data inserted after LOCK TABLE to disappear. (Bug#28838)

Killing an SSL connection on platforms where MySQL is compiled with -DSIGNAL_WITH_VIO_CLOSE (Windows, Mac OS X, and some others) could crash the server. (Bug#28812)

Runtime changes to the log_queries_not_using_indexes system variable were ignored. (Bug#28808)

Tables using the InnoDB storage engine incremented AUTO_INCREMENT values incorrectly with ON DUPLICATE KEY UPDATE. (Bug#28781)

Selecting a column not present in the selected-from table caused an extra error to be produced by SHOW ERRORS. (Bug#28677)

For a statement of the form CREATE t1 SELECT integer_constant, the server created the column using the DECIMAL data type for large negative values that are within the range of BIGINT. (Bug#28625)

For InnoDB tables, MySQL unnecessarily sorted records in certain cases when the records were retrieved by InnoDB in the proper order already. (Bug#28591)

A SELECT in one connection could be blocked by INSERT ... ON DUPLICATE KEY UPDATE in another connection even when low_priority_updates is set. (Bug#28587)

mysql_install_db could fail to find script files that it needs. (Bug#28585)

When one thread attempts to lock two (or more) tables and another thread executes a statement that aborts these locks (such as REPAIR TABLE, OPTIMIZE TABLE, or CHECK TABLE), the thread might get a table object with an incorrect lock type in the table cache. The result is table corruption or a server crash. (Bug#28574)

mysql_upgrade could run binaries dynamically linked against incorrect versions of shared libraries. (Bug#28560)

If a stored procedure was created and invoked prior to selecting a default database with USE, a No database selected error occurred. (Bug#28551)

On Mac OS X, shared-library installation path names were incorrect. (Bug#28544)

Using the --skip-add-drop-table option with mysqldump generated incorrect SQL if the database included any views. The recreation of views requires the creation and removal of temporary tables. This option suppressed the removal of those temporary tables. The same applied to --compact since this option also invokes --skip-add-drop-table. (Bug#28524)

mysqlbinlog --hexdump generated incorrect output due to omission of the “#” comment character for some comment lines. (Bug#28293)

A race condition in the interaction between MyISAM and the query cache code caused the query cache not to invalidate itself for concurrently inserted data. (Bug#28249)

Indexing column prefixes in InnoDB tables could cause table corruption. (Bug#28138)

Index creation could fail due to truncation of key values to the maximum key length rather than to a mulitiple of the maximum character length. (Bug#28125)

The LOCATE() function returned NULL if any of its arguments evaluated to NULL. Likewise, the predicate, LOCATE(str,NULL) IS NULL, erroneously evaluated to FALSE. (Bug#27932)

On Windows, symbols for yaSSL and taocrypt were missing from mysqlclient.lib, resulting in unresolved symbol errors for clients linked against that library. (Bug#27861)

SHOW COLUMNS returned NULL instead of the empty string for the Default value of columns that had no default specified. (Bug#27747)

The modification of a table by a partially completed multi-column update was not recorded in the binlog, rather than being marked by an event and a corresponding error code. (Bug#27716)

With recent versions of DBD::mysql, mysqlhotcopy generated table names that were doubly qualified with the database name. (Bug#27694)

The anonymous accounts were not being created during MySQL installation. (Bug#27692)

Some SHOW statements and INFORMATION_SCHEMA queries could expose information not allowed by the user's access privileges. (Bug#27629)

A stack overrun could occur when storing DATETIME values using repeated prepared statements. (Bug#27592)

Dropping a user-defined function could cause a server crash if the function was still in use by another thread. (Bug#27564)

Some character mappings in the ascii.xml file were incorrect.

As a result of this bug fix, indexes must be rebuilt for columns that use the ascii_general_ci collation for columns that contain any of these characters: '`', '[', '\', ']', '~'. See Section 2.18.3, “Checking Whether Tables or Indexes Must Be Rebuilt”. (Bug#27562)

The parser rules for the SHOW PROFILE statement were revised to work with older versions of bison. (Bug#27433)

Unsafe aliasing in the source caused a client library crash when compiled with gcc 4 at high optimization levels. (Bug#27383)

A SELECT with more than 31 nested dependent subqueries returned an incorrect result. (Bug#27352)

Index-based range reads could fail for comparisons that involved contraction characters (such as ch in Czech or ll in Spanish). (Bug#27345)

Aggregations in subqueries that refer to outer query columns were not always correctly referenced to the proper outer query. (Bug#27333)

INSERT INTO ... SELECT caused a crash if innodb_locks_unsafe_for_binlog was enabled. (Bug#27294)

Error returns from the time() system call were ignored. (Bug#27198)

Phantom reads could occur under InnoDB SERIALIZABLE isolation level. (Bug#27197)

The SUBSTRING() function returned the entire string instead of an empty string when it was called from a stored procedure and when the length parameter was specified by a variable with the value “0”. (Bug#27130)

ALTER TABLE ... ENABLE KEYS could cause mysqld to crash when executed on a table containing on a MyISAM table containing billions of rows. (Bug#27029)

FEDERATED tables had an artificially low maximum of key length. (Bug#26909)

Binary content 0x00 in a BLOB column sometimes became 0x5C 0x00 following a dump and reload, which could cause problems with data using multi-byte character sets such as GBK (Chinese). This was due to a problem with SELECT INTO OUTFILE whereby LOAD DATA later incorrectly interpreted 0x5C as the second byte of a multi-byte sequence rather than as the SOLIDUS (“\”) character, used by MySQL as the escape character. (Bug#26711)

Index creation could corrupt the table definition in the .frm file: 1) A table with the maximum number of key segments and maximum length key name would have a corrupted .frm file, due to incorrect calculation of the total key length. 2) MyISAM would reject a table with the maximum number of keys and the maximum number of key segments in all keys. (It would allow one less than this total maximum.) Now MyISAM accepts a table defined with the maximum. (Bug#26642)

After the first read of a TEMPORARY table, CHECK TABLE could report the table as being corrupt. (Bug#26325)

If an operation had an InnoDB table, and two triggers, AFTER UPDATE and AFTER INSERT, competing for different resources (such as two distinct MyISAM tables), the triggers were unable to execute concurrently. In addition, INSERT and UPDATE statements for the InnoDB table were unable to run concurrently. (Bug#26141)

ALTER DATABASE did not require at least one option. (Bug#25859)

Using HANDLER to open a table having a storage engine not supported by HANDLER properly returned an error, but also improperly prevented the table from being dropped by other connections. (Bug#25856)

The index merge union access algorithm could produce incorrect results with InnoDB tables. The problem could also occur for queries that used DISTINCT. (Bug#25798)

When using a FEDERATED table, the value of LAST_INSERT_ID() would not correctly update the C API interface, which would affect the autogenerated ID returned both through the C API and the MySQL protocol, affecting Connectors that used the protocol and/or C API. (Bug#25714)

The server was blocked from opening other tables while the FEDERATED engine was attempting to open a remote table. Now the server does not check the correctness of a FEDERATED table at CREATE TABLE time, but waits until the table actually is accessed. (Bug#25679)

Under ActiveState Perl, mysql-test-run.pl could kill itself when attempting to kill other processes. (Bug#25657)

Several InnoDB assertion failures were corrected. (Bug#25645)

A query with DISTINCT in the select list to which the loose-scan optimization for grouping queries was applied returned an incorrect result set when the query was used with the SQL_BIG_RESULT option. (Bug#25602)

For a multiple-row insert into a FEDERATED table that refers to a remote transactional table, if the insert failed for a row due to constraint failure, the remote table would contain a partial commit (the rows preceding the failed one) instead of rolling back the statement completely. This occurred because the rows were treated as individual inserts.

Now FEDERATED performs bulk-insert handling such that multiple rows are sent to the remote table in a batch. This provides a performance improvement and enables the remote table to perform statement rollback properly should an error occur. This capability has the following limitations:

(Bug#25513)

The FEDERATED storage engine failed silently for INSERT ... ON DUPLICATE KEY UPDATE if a duplicate key violation occurred. FEDERATED does not support ON DUPLICATE KEY UPDATE, so now it correctly returns an ER_DUP_KEY error if a duplicate key violation occurs. (Bug#25511)

For InnoDB tables, CREATE TABLE a AS SELECT * FROM A would fail. (Bug#25164)

In a stored function or trigger, when InnoDB detected deadlock, it attempted rollback and displayed an incorrect error message (Explicit or implicit commit is not allowed in stored function or trigger). Now InnoDB returns an error under these conditions and does not attempt rollback. Rollback is handled outside of InnoDB above the function/trigger level. (Bug#24989)

A too-long shared-memory-base-name value could cause a buffer overflow and crash the server or clients. (Bug#24924)

Dropping a temporary InnoDB table that had been locked with LOCK TABLES caused a server crash. (Bug#24918)

On Windows, executables did not include Vista manifests. (Bug#24732)

See also Bug#22563.

If MySQL/InnoDB crashed very quickly after starting up, it would not force a checkpoint. In this case, InnoDB would skip crash recovery at next startup, and the database would become corrupt. Now, if the redo log scan at InnoDB startup goes past the last checkpoint, crash recovery is forced. (Bug#23710)

The server deducted some bytes from the key_cache_block_size option value and reduced it to the next lower 512 byte boundary. The resulting block size was not a power of two. Setting the key_cache_block_size system variable to a value that is not a power of two resulted in MyISAM table corruption. (Bug#23068, Bug#28478, Bug#25853)

SHOW INNODB STATUS caused an assertion failure under high load. (Bug#22819)

SHOW BINLOG EVENTS displayed incorrect values of End_log_pos for events associated with transactional storage engines. (Bug#22540)

A statement of the form CREATE TABLE IF NOT EXISTS t1 SELECT f1() AS i failed with a deadlock error if the stored function f1() referred to a table with the same name as the to-be-created table. Now it correctly produces a message that the table already exists. (Bug#22427)

Read lock requests that were blocked by a pending write lock request were not allowed to proceed if the statement requesting the write lock was killed. (Bug#21281)

Under heavy load with a large query cache, invalidating part of the cache could cause the server to freeze (that is, to be unable to service other operations until the invalidation was complete). (Bug#21074)

See also Bug#39253.

mysql-stress-test.pl and mysqld_multi.server.sh were missing from some binary distributions. (Bug#21023, Bug#25486)

On Windows, the server used 10MB of memory for each connection thread, resulting in memory exhaustion. Now each thread uses 1MB. (Bug#20815)

Worked around an icc problem with an incorrect machine instruction being generated in the context of software pre-fetching after a subroutine got in-lined. (Upgrading to icc 10.0.026 makes the workaround unnecessary.) (Bug#20803)

InnoDB produced an unnecessary (and harmless) warning: InnoDB: Error: trying to declare trx to enter InnoDB, but InnoDB: it already is declared. (Bug#20090)

Under ActiveState Perl, mysql-test-run.pl would not run. (Bug#18415)

The server crashed when the size of an ARCHIVE table grew larger than 2GB. (Bug#15787)

SQL_BIG_RESULT had no effect for CREATE TABLE ... SELECT SQL_BIG_RESULT ... statements. (Bug#15130)

On 64-bit Windows systems, the Config Wizard failed to complete the setup because 64-bit Windows does not resolve dynamic linking of the 64-bit libmysql.dll to a 32-bit application like the Config Wizard. (Bug#14649)

mysql_setpermission tried to grant global-only privileges at the database level. (Bug#14618)

Parameters of type DATETIME or DATE in stored procedures were silently converted to VARBINARY. (Bug#13675)

For the general query log, logging of prepared statements executed via the C API differed from logging of prepared statements performed with PREPARE and EXECUTE. Logging for the latter was missing the Prepare and Execute lines. (Bug#13326)

The server returned data from SHOW CREATE TABLE statement or a SELECT statement on an INFORMATION_SCHEMA table using the binary character set. (Bug#10491)

Backup software can cause ERROR_SHARING_VIOLATION or ERROR_LOCK_VIOLATION conditions during file operations. InnoDB now retries forever until the condition goes away. (Bug#9709)