D.2.22 Modifications de la version 3.22.5

  • All table lock handing is changed to avoid some very subtle deadlocks when using DROP TABLE, ALTER TABLE, DELETE FROM TABLE and mysqladmin flush-tables under heavy usage. Changed locking code to get better handling of locks of different types.
  • Updated DBI to 1.00 and DBD to 1.2.0.
  • Added a check that the error message file contains error messages suitable for the current version of mysqld. (To avoid errors if you accidentally try to use an old error message file.)
  • All count structures in the client (affected_rows(), insert_id(),...) are now of type BIGINT to allow 64-bit values to be used. This required a minor change in the MySQL protocol which should affect only old clients when using tables with AUTO_INCREMENT values > 24M.
  • The return type of mysql_fetch_lengths() has changed from uint * to ulong *. This may give a warning for old clients but should work on most machines.
  • Change mysys and dbug libraries to allocate all thread variables in one struct. This makes it easier to make a threaded `libmysql.dll' library.
  • Use the result from gethostname() (instead of uname()) when constructing `.pid' file names.
  • New better compressed server/client protocol.
  • COUNT(), STD() and AVG() are extended to handle more than 4G rows.
  • You can now store values in the range -838:59:59 <= x <= 838:59:59 in a TIME column.
  • WARNING: INCOMPATIBLE CHANGE!! If you set a TIME column to too short a value, MySQL now assumes the value is given as: [[[D ]HH:]MM:]SS instead of HH[:MM[:SS]].
  • TIME_TO_SEC() and SEC_TO_TIME() can now handle negative times and hours up to 32767.
  • Added new option SET OPTION SQL_LOG_UPDATE={0|1} to allow users with the process privilege to bypass the update log. (Modified patch from Sergey A Mukhin violet@rosnet.net.)
  • Fixed fatal bug in LPAD().
  • Initialize line buffer in `mysql.cc' to make BLOB reading from pipes safer.
  • Added -O max_connect_errors=# option to mysqld. Connect errors are now reset for each correct connection.
  • Increased the default value of max_allowed_packet to 1M in mysqld.
  • Added --low-priority-updates option to mysqld, to give UPDATE operations lower priority than retrievals. You can now use {INSERT | REPLACE | UPDATE | DELETE} LOW_PRIORITY ... You can also use SET OPTION LOW_PRIORITY_UPDATES={0|1} to change the priority for one thread. One side effect is that LOW_PRIORITY is now a reserved word. :(
  • Add support for INSERT INTO table ... VALUES(...),(...),(...), to allow inserting multiple rows with a single statement.
  • INSERT INTO nom_table is now also cached when used with LOCK TABLES. (Previously only INSERT ... SELECT and LOAD DATA INFILE were cached.)
  • Allow GROUP BY functions with HAVING: 
    mysql> SELECT col FROM table GROUP BY col HAVING COUNT(*)>0;
  • mysqld will now ignore trailing `;' characters in queries. This is to make it easier to migrate from some other SQL servers that require the trailing `;'.
  • Fix for corrupted fixed-format output generated by SELECT INTO OUTFILE.
  • WARNING: INCOMPATIBLE CHANGE!! Added Oracle GREATEST() and LEAST() functions. You must now use these instead of the MAX() and MIN() functions to get the largest/smallest value from a list of values. These can now handle REAL, BIGINT and string (CHAR or VARCHAR) values.
  • WARNING: INCOMPATIBLE CHANGE!! DAYOFWEEK() had offset 0 for Sunday. Changed the offset to 1.
  • Give an error for requêtesthat mix GROUP BY columns and fields when there is no GROUP BY specification.
  • Added --vertical option to mysql, for printing results in vertical mode.
  • Index-only optimization; some requêtesare now resolved using only indexes. Until MySQL 4.0, this works only for numeric columns. MySQL indexes.
  • Lots of new benchmarks.
  • A new C API chapter and lots of other improvements in the manual.