The main differences between MySQL 4.1/5.0/5.1/5.5/5.6 versions

The main differences between MySQL 4.1/5.0/5.1/5.5/5.6 versions

5.0 increased the support of stored procedures, views, Cursors, Triggers, XA transactions, and added the Inforation_schema system database.

Second, 5.1 added event scheduler,partitioning,pluggable storage engine API, row-based replication, global level dynamically modify general query Log and slow query log support.

The main differences between MySQL 4.1/5.0/5.1/5.5/5.6 versions

1, 4.1 added support for subqueries, the character set increase Utf-8,group by statement increased the Rollup,mysql.user table using a better encryption algorithm.

2, 5.0 increased the stored procedures, views, Cursors, Triggers, XA transactions support, increased the Inforation_schema system database.

3, 5.1 added event scheduler,partitioning,pluggable storage engine API, row-based replication, global level dynamically modify general query Log and slow query log support.

New features of 4 and 5.5

1) Change the default storage engine to InnoDB

2) Improved performance and scalability

A. Increased number of default thread concurrency (innodb_thread_concurrency)

B. Background input/Output line program control (innodb_read_io_threads, Innodb_write_io_threads)

C. Main thread input/output rate control (innodb_io_capacity)

D. Operating system memory allocation Program usage control (INNODB_USE_SYS_MALLOC)

E. Adaptive hash Index (hash index) control, the user can turn off the adaptive hashing function.

F. Insertion buffer (insert buffering) control, the user can turn off the InnoDB insertion buffer function.

G. By using the fast lock algorithm to improve scalability, InnoDB does not use proxy (POSIX) threads, but instead uses native standalone operations to complete mutex and read-write locking.

H. Recovery Group commit (restored group commit)

I. Improving recovery performance

J. Multi-buffer pool instances

K. Multiple rollback segments (multiple Rollback segments), the previous InnoDB version can handle up to 1023 concurrent processing operations, now mysql5.5 can handle up to 128K of concurrent things,

L. The asynchronous input/output inherent to the Linux system, the mysql5.5 database system also increases the number of concurrent input and output requests for the Linux system.

M. Extended change buffering: Added delete buffer and purge buffer

N. Improved log system mutex and separate flush list mutex

O. Improve the cleanup progress, in mysql5.5 clear that the operation thread is a separate thread, and supports concurrency, you can use the Innodb_purge_treads configuration.

P. Improve metadata locking in transactional processing. For example, a statement in a thing that needs to lock a table will release the table at the end of the thing, rather than releasing the table at the end of the statement as before.

3) Improve usability

A. Semi-synchronous replication (semi-synchronous Replication)

B. Copy Heartbeat

C. Automatic relay Log recovery (Automatic Relay log Recovery)

D. Replication based on server filtering (Replication per server Filtering)

E. Replication of supported data type conversions from the server (Replication Slave, Side data, type Conversions)

4) Improve manageability and efficiency

A. Establishing a quick index (Faster index Creation)

B. Efficient data compression (efficient Compression)

C. Providing efficient storage for large objects and variable-length columns

D. The Information_schema table is added, and the new table provides specific information about INNODB compression and transaction locking.

5) Improved usability

A. New SQL syntax for signal/resignal

B. New Table/Index partitioning options. MySQL5.5 extends the table and index rang and list partition ranges to non-integer columns and dates, and increases the ability to partition on multiple columns.

6) improved detection and diagnosis

MYSQL5.5 introduces a new performance architecture (performancn_shema,p_s) to monitor the performance of the MySQL monitoring server runtime.

5, 5.6 new features 1) InnoDB can now limit the number of memory-intensive issues (such as those mentioned here) when large numbers of tables are opened (for example, a third party already has patches)
2) InnoDB performance enhancement. such as split kernel Mutex;flush operation from the main thread separation; multiple perge threads; large memory optimization, etc.
3) InnoDB deadlock information can be logged to the error log for easy analysis
4) MySQL5.6 supports time-lapse replication, which allows the slave to control an interval with master, allowing for data recovery in special cases.
5) Table Partitioning enhancements
6) MySQL row-level replication is enhanced to reduce resource overhead such as disk, memory, and network (only fields that determine Row records can be recorded)
7) Binlog Implementation Crash-safe
8) Replication events with CRC32 checksum to enhance Master/slave replication data consistency
9) added Log_bin_basename (previously variables there is no Binlog location information, the monitoring of the database is very inconvenient)

MySQL 5.7 has been in development for two years. There are a lot of improvements compared to MySQL 5.6. The team focuses on speed and performance is reported to be 2 to 3 times times higher than previous versions!
New Feature List, main improvements:
Improve MySQL Security

Improved the Setup program
In MySQL 5.6, MYSQL_INSTALL_DB provides the option to generate the random password when the database is created.
In MySQL 5.7.4, you can skip the-skip-random-password option to generate a random password by default.
MySQL 5.7.5, or generate a random password by default, but the option is modified to –insecure
Now, MySQL 5.7.6 abandoned mysql_install_db, using Mysqld–initialize (formerly known as "Mysqld–bootstrap," then deprecated.) instead.

The main differences between MySQL 4.1/5.0/5.1/5.5/5.6 versions