MYSQL 5.6新特性介绍

官方参考：
http://dev.mysql.com/doc/refman/5.6/en/mysql-nutshell.html

一、大的方面变动：

1、新增字典表，InnoDB buffer pool 相关(评：可深入了解)
Several new InnoDB-related INFORMATION_SCHEMA tables provide information about the InnoDB buffer pool, metadata about tables, indexes, and foreign keys from the InnoDB data dictionary, and low-level information about performance metrics that complements the information from the Performance Schema tables.

2、执行计划优化? (评：可持续关注)
Optimizer statistics for InnoDB tables can now persist across server restarts, for improved plan stability. You can also control the amount of sampling done for InnoDB indexes, to make the optimizer statistics more accurate and improve the query execution plan.

3、多表打开优化
InnoDB now limits the memory used to hold table information when many tables are opened

4、内部优化
InnoDB has several internal performance enhancements, including reducing contention by splitting the kernel mutex, moving flushing operations from the main thread to a separate thread, enabling multiple purge threads, and reducing contention for the buffer pool on large-memory systems.

5、死锁写入log
Information about all InnoDB deadlocks can be written to the MySQL server error log, to help diagnose application issues.

二、分区表方面(注：越来越接近ORACLE分区表了)

1、分区交换 (评：想用的功能)
It is now possible to exchange a partition of a partitioned table or a subpartition of a subpartitioned table with a nonpartitioned table

2、在SELECT等dml中指定查询的分区
Explicit selection of one or more partitions or subpartitions is now supported for queries, as well as for many data modification statements, that act on partitioned tables. For example, assume a table t with some integer column c has 4 partitions named p0, p1, p2, and p3. Then the query SELECT * FROM t PARTITION (p0, p1) WHERE c < 5 returns only those rows from partitions p0 and p1 for which c is less than 5.

三、性能方面

(评：看能得到哪些数据，用以监控分析)

Performance Schema.? The Performance Schema includes several new features:
Instrumentation for table input and output. Instrumented operations include row-level accesses to persistent base tables or temporary tables. Operations that affect rows are fetch, insert, update, and delete.
关注：
Event filtering by table, based on schema and/or table names.
关注：
Event filtering by thread. More information is collected for threads.
关注：
Summary tables for table and index I/O, and for table locks.
关注：
Instrumentation for statements and stages within statements.

Configuration of instruments and consumers at server startup, which previously was possible only at runtime.

四、复制方面

Replication and logging.? These replication enhancements were added:

MySQL row-based replication now supports row image control. By logging only those columns required for uniquely identifying and executing changes on each row (as opposed to all columns) for each row change, it is possible to save disk space, network resources, and memory usage. You can determine whether full or minimal rows are logged by setting the binlog_row_image server system variable to one of the values minimal (log required columns only), full (log all columns), or noblob (log all columns except for unneeded BLOB or TEXT columns). See System variables used with the binary log, for more information.