MOD() no longer rounds arguments with a fractional part to integers. Now it returns exact remainder after division. (Bug#6138)

InnoDB: Added a startup option and settable system variable innodb_table_locks for making LOCK TABLE acquire also InnoDB locks. The default value is 1, which means that LOCK TABLES causes also InnoDB internally to take a table lock. In applications using AUTOCOMMIT=1 and LOCK TABLES, InnoDB's internal table locks that were added in 4.0.20 and 4.1.2 can cause deadlocks. You can set innodb_table_locks=0 in my.cnf to remove that problem. (Bug#3299, Bug#5998)

See Section 14.2.17, “Restrictions on InnoDB Tables”. (Bug#3299, Bug#5998) InnoDB: SHOW TABLE STATUS now shows the creation time of the table for InnoDB. Note that this timestamp might not be the correct time because, for example, ALTER TABLE changes this timestamp.

InnoDB: If innodb_thread_concurrency would be exceeded, let a thread sleep 10 ms before entering the FIFO queue; previously, the value was 50 ms.

Fixed a bug with FOUND_ROWS() used together with LIMIT clause in prepared statements. (Bug#6088)

Fixed a bug with NATURAL JOIN in prepared statements. (Bug#6046).

Fixed a bug in join of tables from different databases having columns with identical names (prepared statements). (Bug#6050)

Now implicit access to system time zone description tables (which happens when you set the time_zone variable or use CONVERT_TZ() function) does not require any privileges. (Bug#6116)

Fixed a bug which caused the server to crash when the deprecated libmysqlclient function mysql_create_db() was called. (Bug#6081)

Fixed REVOKE ALL PRIVILEGES, GRANT OPTION FROM user so that all privileges are revoked correctly. (Bug#5831). This corrects a case that the fix in 4.1.6 could miss.

Fixed crash when selecting from a HEAP table with key_column IS NOT NULL. This could also cause a crash if not all index parts where used. (Bug#6082)

Fixed a bug that could cause MyISAM index corruption when key values start with character codes below BLANK. This was caused by the new key sort order in 4.1. (Bug#6151)

InnoDB: Fixed a bug in LOAD DATA INFILE…REPLACE printing duplicate key error when executing the same load query several times. (Bug#5835)

Fixed a bug in the prepared statements protocol when wrong metadata was sent for SELECT statements not returning a result set (such as SELECT ... INTO OUTFILE). (Bug#6059)

Fixed bug which allowed one to circumvent missing UPDATE privilege if one had INSERT and SELECT privileges for table with primary key. (Bug#6173)

Fixed a bug in libmysqlclient with wrong conversion of negative time values to strings. (Bug#6049).

Fixed a bug in libmysqlclient with wrong conversion of zero date values (0000-00-00) to strings. (Bug#6058)

Fixed a bug that caused the server to crash on attempt to prepare a statement with RAND(?). (Bug#5985)

Fixed a bug with handling of DATE, TIME, and DATETIME columns in the binary protocol. The problem is compiler-specific and could have been observed on HP-UX, AIX, Solaris9, when compiling with native compiler. (Bug#6025)

Fixed a bug with handling of TINYINT columns in the binary protocol. The problem is specific to platforms where the C compiler has the char data type unsigned by default. (Bug#6024)

InnoDB: Fixed problem introduced in MySQL 4.0.21 where a connection starting a transaction, doing updates, then FLUSH TABLES WITH READ LOCK, then COMMIT, would cause replication slaves to stop (complaining about error 1223). Bug surfaced when using the InnoDB innobackup script. (Bug#5949)

InnoDB: Release the dictionary latch during a long cascaded FOREIGN KEY operation, so that we do not starve other users doing CREATE TABLE or other DDL operation. This caused a notorious 'Long semaphore wait' message to be printed to the .err log. (Bug#5961)