This section summarizes what has been added to MySQL 5.1 and what has been deprecated for further use.
The following features have been added to MySQL 5.1:
This capability enables distributing portions of individual
tables across a file system, according to rules which can be
set when the table is created. In effect, different portions
of a table are stored as separate tables in different
locations, but from the user point of view, the partitioned
table is still a single table. Syntactically, this
implements a number of new extensions to the
ALTER TABLE, and
EXPLAIN ... SELECT statements. As of
MySQL 5.1.6, queries against partitioned tables can take
advantage of partition pruning. In some
cases, this can result in query execution that is an order
of magnitude faster than the same query against a
nonpartitioned version of the same table. See
Chapter 18, Partitioning, for further information on
this functionality. (Author: Mikael Ronström)
Row-based replication. Replication capabilities in MySQL originally were based on propagation of SQL statements from master to slave. This is called statement-based replication. As of MySQL 5.1.5, another basis for replication is available. This is called row-based replication. Instead of sending SQL statements to the slave, the master writes events to its binary log that indicate how individual table rows are effected. As of MySQL 5.1.8, a third option is available: mixed. This will use statement-based replication by default, and only switch to row-based replication in particular cases. See Section 16.1.2, “Replication Formats”. (Authors: Lars Thalmann, Guilhem Bichot, Mats Kindahl)
Plugin API. MySQL 5.1 adds support for a very flexible plugin API that enables loading and unloading of various components at runtime, without restarting the server. Although the work on this is not finished yet, plugin full-text parsers are a first step in this direction. This permits users to implement their own input filter on the indexed text, enabling full-text search capability on arbitrary data such as PDF files or other document formats. A pre-parser full-text plugin performs the actual parsing and extraction of the text and hands it over to the built-in MySQL full-text search. See Section 22.2, “The MySQL Plugin API”. (Author: Sergey Vojtovich)
MySQL Events are tasks that run according to a schedule.
When you create an event, you are creating a named database
object containing one or more SQL statements to be executed
at one or more regular intervals, beginning and ending at a
specific date and time. Conceptually, this is similar to the
idea of the Unix
crontab (also known as a
“cron job”) or the Windows Task Scheduler. See
Section 19.4, “Using the Event Scheduler”. (Author: Andrey Hristov)
Server log tables.
Before MySQL 5.1, the server writes general query log and
slow query log entries to log files. As of MySQL 5.1, the
server's logging capabilities for these logs are more
flexible. Log entries can be written to log files (as
before) or to the
slow_log tables in the
mysql database. If logging is enabled,
either or both destinations can be selected. The
--log-output option controls
the destination or destinations of log output. See
Section 5.2.1, “Selecting General Query and Slow Query Log Output Destinations”. (Author: Petr Chardin)
Upgrade program. The mysql_upgrade program (available as of MySQL 5.1.7) checks all existing tables for incompatibilities with the current version of MySQL Server and repairs them if necessary. This program should be run for each MySQL upgrade. See Section 4.4.8, “mysql_upgrade — Check and Upgrade MySQL Tables”. (Authors: Alexey Botchkov, Mikael Widenius)
MySQL Cluster is now released as a separate product, based
on MySQL 5.1 but with the addition of the
NDBCLUSTER storage engine.
Clustering support is no longer available in mainline MySQL
5.1 releases. MySQL Cluster releases are identified by a
3-part NDB version number; currently, the MySQL Cluster NDB
6.3, MySQL Cluster NDB 7.0, and MySQL Cluster NDB 7.1
release series are available for production use.
Some of the changes in MySQL Cluster since MySQL 5.0 are listed here:
MySQL Cluster replication. Replication between MySQL Clusters is now supported. It is now also possible to replicate between a MySQL Cluster and a noncluster database. See Section 17.6, “MySQL Cluster Replication”.
MySQL Cluster disk data storage.
storage engine was strictly in-memory; now, it is
possible to store Cluster data (but not indexes) on
disk. This enables MySQL Cluster to scale upward with
fewer hardware (RAM) requirements than previously. In
addition, the Disk Data implementation includes a new
“no-steal” restoration algorithm for fast
node restarts when storing very large amounts of data
(terabyte range). See
Section 17.5.12, “MySQL Cluster Disk Data Tables”, for more
Improved backups for MySQL Cluster. A fault arising in a single data node during a Cluster backup no longer causes the entire backup to be aborted, as occurred in previous versions of MySQL Cluster.
Many other new features and improvements have been made to the
NDBCLUSTER storage engine in
MySQL Cluster NDB 7.0 and MySQL Cluster NDB 7.1; for more
information about these, see
Section 17.1.4, “MySQL Cluster Development History”.
Improvements to INFORMATION_SCHEMA.
MySQL 5.1 provides much more information in its metadata
database than was available in MySQL 5.0. New tables in the
INFORMATION_SCHEMA database include
XML functions with XPath support.
ExtractValue() returns the
content of a fragment of XML matching a given XPath
replaces the element selected from a fragment of XML by an
XPath expression supplied by the user with a second XML
fragment (also user-supplied), and returns the modified XML.
See Section 12.11, “XML Functions”. (Author: Alexander
Load emulator. The mysqlslap program is designed to emulate client load for a MySQL server and report the timing of each stage. It works as if multiple clients were accessing the server. See Section 4.5.7, “mysqlslap — Load Emulation Client”. (Authors: Patrick Galbraith, Brian Aker)
The following constructs are deprecated in MySQL 5.1 and are removed as of MySQL 5.5. Where alternatives are shown, applications should be updated to use them.
SHOW TABLE TYPES SQL statement (use
SHOW PLUGIN SQL statement (use
data type: The ability to specify a display width of
N (use without
server options to set replication parameters (use the
CHANGE MASTER TO statement