TiDB 1.1 Alpha Release Notes
On January 19, 2018, TiDB 1.1 Alpha is released. This release has great improvement in MySQL compatibility, SQL optimization, stability, and performance.
TiDB
- SQL parser
- Support more syntax
 
 - SQL query optimizer
- Use more compact structure to reduce statistics info memory usage
 - Speed up loading statistics info when starting tidb-server
 - Provide more accurate query cost evaluation
 - Use 
Count-Min Sketchto estimate the cost of queries using unique index more accurately - Support more complex conditions to make full use of index
 
 - SQL executor
- Refactor all executor operators using Chunk architecture, improve the execution performance of analytical statements and reduce memory usage
 - Optimize performance of the 
INSERT IGNOREstatement - Push down more types and functions to TiKV
 - Support more 
SQL_MODE - Optimize the 
Load Dataperformance to increase the speed by 10 times - Optimize the 
Use Databaseperformance - Support statistics on the memory usage of physical operators
 
 - Server
- Support the PROXY protocol
 
 
PD
- Add more APIs
 - Support TLS
 - Add more cases for scheduling Simulator
 - Schedule to adapt to different Region sizes
 - Fix some bugs about scheduling
 
TiKV
- Support Raft learner
 - Optimize Raft Snapshot and reduce the I/O overhead
 - Support TLS
 - Optimize the RocksDB configuration to improve performance
 - Optimize 
count (*)and query performance of unique index in Coprocessor - Add more failpoints and stability test cases
 - Solve the reconnection issue between PD and TiKV
 - Enhance the features of the data recovery tool 
tikv-ctl - Support splitting according to table in Region
 - Support the 
Delete Rangefeature - Support setting the I/O limit caused by snapshot
 - Improve the flow control mechanism