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TiDB Roadmap
Learn about the roadmap of TiDB.

TiDB Roadmap

This document defines the roadmap for TiDB development.


  • Optimizer
    • Refactor Ranger
    • Optimize the cost model
    • Cascades model planner
    • Join Reorder
  • Statistics
    • Update statistics dynamically according to the query feedback
    • Analyze table automatically
    • Improve the accuracy of Row Count estimation
  • Execution Engine
    • Push down the Projection operator to the Coprocessor
    • Improve the performance of the HashJoin operator
    • Parallel Operators
      • Projection
      • Aggregation
      • Sort
    • Compact Row Format to reduce memory usage
    • File Sort
  • View
  • Window Function
  • Common Table Expression
  • Table Partition
    • Range Partition
    • Hash Partition
  • Cluster Index
  • New storage row format
  • Query Tracing
  • Improve DDL
    • Speed up Add Index operation
    • Parallel DDL
    • Support locking table
    • Support modifying the column type
    • Supoort modifying the primary key
    • Support multiple DDL operations in a single statement
  • Support utf8_general_ci collation


  • Raft
    • Region Merge - Merge small Regions together to reduce overhead
    • Local Read Thread - Process read requests in a local read thread
    • Split Region in Batch - Speed up Region split for large Regions
    • Raft Learner - Support Raft learner to smooth the configuration change process
    • Raft Pre-vote - Support Raft pre-vote to avoid unnecessary leader election on network isolation
    • Joint Consensus - Change multi members safely.
    • Multi-thread Raftstore - Process Region Raft logic in multiple threads
    • Multi-thread apply pool - Apply Region Raft committed entries in multiple threads
  • Engine
    • Titan - Separate large key-values from LSM-Tree
    • Pluggable Engine Interface - Clean up the engine wrapper code and provide more extensibility
  • Storage
    • Flow Control - Do flow control in scheduler to avoid write stall in advance
  • Transaction
    • Optimize transaction conflicts
    • Distributed GC - Distribute MVCC garbage collection control to TiKV
  • Coprocessor
    • Streaming - Cut large data set into small chunks to optimize memory consumption
    • Chunk Execution - Process data in chunk to improve performance
    • Request Tracing - Provide per-request execution details
  • Tools
    • TiKV Importer - Speed up data importing by SST file ingestion
  • Client
    • TiKV client (Rust crate)
    • Batch gRPC Message - Reduce message overhead


  • Improve namespace
    • Different replication policies for different namespaces and tables
  • Decentralize scheduling table Regions
  • Scheduler supports prioritization to be more controllable
  • Use machine learning to optimize scheduling
  • Optimize Region metadata - Save Region metadata in detached storage engine


  • Limit/Order push-down
  • Access through the DAG interface and deprecate the Select interface
  • Index Join and parallel merge join
  • Data Federation


  • Tool for automating TiDB deployment
  • High-Performance data import tool (lightning)
  • Backup and restore tool (incremental backup supported by drainer, incremental restore supported by reparo)
  • New TiDB-binlog with improved architecture
  • Data online migration tool (premium edition of Syncer)
  • Diagnostic tools