TiDB RC1 Release Notes

On December 23, 2016, TiDB RC1 is released. See the following updates in this release:

TiKV

  • The write speed has been improved.
  • The disk space usage is reduced.
  • Hundreds of TBs of data can be supported.
  • The stability is improved and TiKV can support a cluster with 200 nodes.
  • Supports the Raw KV API and the Golang client.

Placement Driver (PD)

  • The scheduling strategy framework is optimized and now the strategy is more flexible and reasonable.
  • The support for label is added to support Cross Data Center scheduling.
  • PD Controller is provided to operate the PD cluster more easily.

TiDB

  • The following features are added or improved in the SQL query optimizer:
    • Eager aggregation
    • More detailed EXPLAIN information
    • Parallelization of the UNION operator
    • Optimization of the subquery performance
    • Optimization of the conditional push-down
    • Optimization of the Cost Based Optimizer (CBO) framework
  • The implementation of the time related data types are refactored to improve the compatibility with MySQL.
  • More built-in functions in MySQL are supported.
  • The speed of the add index statement is enhanced.
  • The following statements are supported:
    • Use the CHANGE COLUMN statement to change the name of a column.
    • Use MODIFY COLUMN and CHANGE COLUMN of the ALTER TABLE statement for some of the column type transfer.

New tools

  • Loader is added to be compatible with the mydumper data format in Percona and provides the following functions:
    • Multi-thread import
    • Retry if error occurs
    • Breakpoint resume
    • Targeted optimization for TiDB
  • The tool for one-click deployment is added.