# TiDB Release Notes > This document lists all released TiDB versions, sorted by version number in descending order. ## OVERVIEW - [Release Timeline](https://docs.pingcap.com/tidb/stable/release-timeline.md): Learn about the TiDB release timeline. - [TiDB Versioning](https://docs.pingcap.com/tidb/stable/versioning.md): Learn the version numbering system of TiDB. - [Release Support Policy](https://www.pingcap.com/tidb-release-support-policy/) ## RELEASE NOTES - v8.5 - [8.5.5](https://docs.pingcap.com/tidb/stable/release-8.5.5.md): Learn about the features, compatibility changes, improvements, and bug fixes in TiDB 8.5.5. - [8.5.4](https://docs.pingcap.com/tidb/stable/release-8.5.4.md): Learn about the features, compatibility changes, improvements, and bug fixes in TiDB 8.5.4. - [8.5.3](https://docs.pingcap.com/tidb/stable/release-8.5.3.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 8.5.3. - [8.5.2](https://docs.pingcap.com/tidb/stable/release-8.5.2.md): Learn about the improvements and bug fixes in TiDB 8.5.2. - [8.5.1](https://docs.pingcap.com/tidb/stable/release-8.5.1.md): Learn about the operating system and platform requirement changes, compatibility changes, improvements, and bug fixes in TiDB 8.5.1. - [8.5.0](https://docs.pingcap.com/tidb/stable/release-8.5.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.5.0. - v8.4 - [8.4.0-DMR](https://docs.pingcap.com/tidb/stable/release-8.4.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.4.0. - v8.3 - [8.3.0-DMR](https://docs.pingcap.com/tidb/stable/release-8.3.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.3.0. - v8.2 - [8.2.0-DMR](https://docs.pingcap.com/tidb/stable/release-8.2.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.2.0. - v8.1 - [8.1.2](https://docs.pingcap.com/tidb/stable/release-8.1.2.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 8.1.2. - [8.1.1](https://docs.pingcap.com/tidb/stable/release-8.1.1.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 8.1.1. - [8.1.0](https://docs.pingcap.com/tidb/stable/release-8.1.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.1.0. - v8.0 - [8.0.0-DMR](https://docs.pingcap.com/tidb/stable/release-8.0.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 8.0.0. - v7.6 - [7.6.0-DMR](https://docs.pingcap.com/tidb/stable/release-7.6.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.6.0. - v7.5 - [7.5.7](https://docs.pingcap.com/tidb/stable/release-7.5.7.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.7. - [7.5.6](https://docs.pingcap.com/tidb/stable/release-7.5.6.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.6. - [7.5.5](https://docs.pingcap.com/tidb/stable/release-7.5.5.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.5. - [7.5.4](https://docs.pingcap.com/tidb/stable/release-7.5.4.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.4. - [7.5.3](https://docs.pingcap.com/tidb/stable/release-7.5.3.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.3. - [7.5.2](https://docs.pingcap.com/tidb/stable/release-7.5.2.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.2. - [7.5.1](https://docs.pingcap.com/tidb/stable/release-7.5.1.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.5.1. - [7.5.0](https://docs.pingcap.com/tidb/stable/release-7.5.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.5.0. - v7.4 - [7.4.0-DMR](https://docs.pingcap.com/tidb/stable/release-7.4.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.4.0. - v7.3 - [7.3.0-DMR](https://docs.pingcap.com/tidb/stable/release-7.3.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.3.0. - v7.2 - [7.2.0-DMR](https://docs.pingcap.com/tidb/stable/release-7.2.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.2.0. - v7.1 - [7.1.6](https://docs.pingcap.com/tidb/stable/release-7.1.6.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.6. - [7.1.5](https://docs.pingcap.com/tidb/stable/release-7.1.5.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.5. - [7.1.4](https://docs.pingcap.com/tidb/stable/release-7.1.4.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.4. - [7.1.3](https://docs.pingcap.com/tidb/stable/release-7.1.3.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.3. - [7.1.2](https://docs.pingcap.com/tidb/stable/release-7.1.2.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.2. - [7.1.1](https://docs.pingcap.com/tidb/stable/release-7.1.1.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 7.1.1. - [7.1.0](https://docs.pingcap.com/tidb/stable/release-7.1.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.1.0. - v7.0 - [7.0.0-DMR](https://docs.pingcap.com/tidb/stable/release-7.0.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 7.0.0. - v6.6 - [6.6.0-DMR](https://docs.pingcap.com/tidb/stable/release-6.6.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 6.6.0. - v6.5 - [6.5.12](https://docs.pingcap.com/tidb/stable/release-6.5.12.md): Learn about the improvements and bug fixes in TiDB 6.5.12. - [6.5.11](https://docs.pingcap.com/tidb/stable/release-6.5.11.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.11. - [6.5.10](https://docs.pingcap.com/tidb/stable/release-6.5.10.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.10. - [6.5.9](https://docs.pingcap.com/tidb/stable/release-6.5.9.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.9. - [6.5.8](https://docs.pingcap.com/tidb/stable/release-6.5.8.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.8. - [6.5.7](https://docs.pingcap.com/tidb/stable/release-6.5.7.md): Learn about the improvements and bug fixes in TiDB 6.5.7. - [6.5.6](https://docs.pingcap.com/tidb/stable/release-6.5.6.md): Learn about the improvements and bug fixes in TiDB 6.5.6. - [6.5.5](https://docs.pingcap.com/tidb/stable/release-6.5.5.md): Learn about the improvements and bug fixes in TiDB 6.5.5. - [6.5.4](https://docs.pingcap.com/tidb/stable/release-6.5.4.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.4. - [6.5.3](https://docs.pingcap.com/tidb/stable/release-6.5.3.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.3. - [6.5.2](https://docs.pingcap.com/tidb/stable/release-6.5.2.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.2. - [6.5.1](https://docs.pingcap.com/tidb/stable/release-6.5.1.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.5.1. - [6.5.0](https://docs.pingcap.com/tidb/stable/release-6.5.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 6.5.0. - v6.4 - [6.4.0-DMR](https://docs.pingcap.com/tidb/stable/release-6.4.0.md): TiDB 6.4.0-DMR introduces new features and improvements, including support for restoring a cluster to a specific point in time, compatibility with Linear Hash partitioning syntax, and a high-performance `AUTO_INCREMENT` mode. It also enhances fault recovery, memory usage control, and statistics collection. TiFlash now supports the SM4 algorithm for encryption at rest, and TiCDC supports replicating data to Kafka. The release also includes bug fixes and improvements across various tools and components. - v6.3 - [6.3.0-DMR](https://docs.pingcap.com/tidb/stable/release-6.3.0.md): TiDB 6.3.0-DMR, released on September 30, 2022, introduces new features and improvements, including encryption at rest using the SM4 algorithm in TiKV, authentication using the SM3 algorithm in TiDB, and support for JSON data type and functions. It also provides execution time metrics at a finer granularity, enhances output for slow logs and `TRACE` statements, and supports deadlock history information in TiDB Dashboard. Additionally, TiDB v6.3.0 introduces new system variables and configuration file parameters, and fixes various bugs and issues. The release also includes improvements in TiKV, PD, TiFlash, Backup & Restore (BR), TiCDC, TiDB Binlog, TiDB Data Migration (DM), and TiDB Lightning. - v6.2 - [6.2.0-DMR](https://docs.pingcap.com/tidb/stable/release-6.2.0.md): TiDB 6.2.0-DMR introduces new features like visual execution plans, monitoring page, and lock view. It also supports concurrent DDL operations and enhances the performance of aggregation operations. TiKV now supports automatic CPU usage tuning and detailed configuration information listing. TiFlash adds FastScan for data scanning and improves error handling. BR now supports continuous data validation and automatically identifies the region of Amazon S3 buckets. TiCDC supports filtering DDL and DML events. There are also compatibility changes, bug fixes, and improvements across various tools. - v6.1 - [6.1.7](https://docs.pingcap.com/tidb/stable/release-6.1.7.md): Learn about the improvements and bug fixes in TiDB 6.1.7. - [6.1.6](https://docs.pingcap.com/tidb/stable/release-6.1.6.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.1.6. - [6.1.5](https://docs.pingcap.com/tidb/stable/release-6.1.5.md): Learn about the compatibility changes, improvements, and bug fixes in TiDB 6.1.5. - [6.1.4](https://docs.pingcap.com/tidb/stable/release-6.1.4.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 6.1.4. - [6.1.3](https://docs.pingcap.com/tidb/stable/release-6.1.3.md): TiDB 6.1.3 was released on December 5, 2022. The release includes compatibility changes, improvements, bug fixes, and updates to various tools such as TiCDC, PD, TiKV, TiFlash, Backup & Restore, TiCDC, and TiDB Data Migration. Some notable changes include default value changes in TiCDC, lock granularity optimization in PD, and bug fixes in TiDB, PD, TiKV, TiFlash, and various tools. The release also includes an upgrade to the Go compiler version of TiDB from go1.18 to go1.19, which improves stability. - [6.1.2](https://docs.pingcap.com/tidb/stable/release-6.1.2.md): TiDB 6.1.2 was released on October 24, 2022. The release includes improvements to TiDB, TiKV, Tools, PD, TiFlash, and bug fixes for various issues in each component. The improvements include setting placement rules and TiFlash replicas simultaneously, support for configuring various settings, and enhancing performance. Bug fixes address issues such as incorrect cleanup of privileges, incorrect output, query failures, and performance issues. - [6.1.1](https://docs.pingcap.com/tidb/stable/release-6.1.1.md): TiDB 6.1.1 was released on September 1, 2022. Changes include case-insensitive `SHOW DATABASES LIKE` statement, default value change for `tidb_enable_outer_join_reorder`, and improvements in optimizer and metrics response compression. Bug fixes address issues such as hanging `INL_HASH_JOIN`, panicking during `UPDATE` statement execution, and incorrect query results. Other changes include multi-level support for different quality standards and additions to the `TiDB-community-toolkit` binary package. - [6.1.0](https://docs.pingcap.com/tidb/stable/release-6.1.0.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 6.1.0. - v6.0 - [6.0.0-DMR](https://docs.pingcap.com/tidb/stable/release-6.0.0-dmr.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 6.0.0. - v5.4 - [5.4.3](https://docs.pingcap.com/tidb/stable/release-5.4.3.md): TiDB 5.4.3 was released on October 13, 2022. The release includes various improvements and bug fixes for TiKV, Tools, TiCDC, TiFlash, PD, and other tools. Improvements include support for configuring RocksDB write stall settings, optimizing Scatter Region to batch mode, and reducing performance overhead in multi-Region scenarios. Bug fixes address issues such as incorrect output of `SHOW CREATE PLACEMENT POLICY`, DDL statements getting stuck after PD node replacement, and various issues causing incorrect results and errors in TiDB, TiKV, PD, TiFlash, and other tools. The release also provides workarounds and affected versions for specific issues. - [5.4.2](https://docs.pingcap.com/tidb/stable/release-5.4.2.md): TiDB 5.4.2 was released on July 8, 2022. It is not recommended to use this version due to a known bug, which has been fixed in v5.4.3. The release includes improvements to TiDB, TiKV, PD, and various tools, along with bug fixes for each component. These bug fixes address issues related to stability, performance, and error handling. - [5.4.1](https://docs.pingcap.com/tidb/stable/release-5.4.1.md): TiDB 5.4.1 Release Notes: This release includes compatibility changes, improvements, and bug fixes for TiDB, TiKV, PD, TiFlash, and various tools. Improvements include support for using the PointGet plan, adding more logs and metrics, and displaying multiple Kubernetes clusters in the Grafana dashboard. Bug fixes address issues such as incorrect handling of date_format, wrong data writing, wrong query results, and various panics and errors. Fixes for TiKV, PD, TiFlash, and tools are also included. - [5.4.0](https://docs.pingcap.com/tidb/stable/release-5.4.0.md): TiDB 5.4 introduces support for the GBK character set, Index Merge, reading stale data, persisting statistics configuration, and using Raft Engine as the log storage engine of TiKV. It also improves backup impact, supports Azure Blob storage, and enhances TiFlash and the MPP engine. Compatibility changes include new system variables and configuration file parameters. Other improvements cover SQL, security, performance, stability, high availability, data migration, diagnostic efficiency, and deployment. Bug fixes address issues in TiDB, TiKV, PD, TiFlash, BR, TiCDC, DM, TiDB Lightning, and TiDB Binlog. - End of Life Releases - v5.3 - [5.3.4](https://docs.pingcap.com/tidb/stable/release-5.3.4.md): TiDB 5.3.4 was released on November 24, 2022. The release includes improvements to TiKV and bug fixes for TiDB, PD, TiFlash, Dumpling, and TiCDC. Some of the key bug fixes include issues related to TLS certificate reloading, Region cache cleanup, wrong data writing, database-level privileges, and authentication failures. Other fixes address issues with logical operators, stream timeout, leader switchover, and data dumping. - [5.3.3](https://docs.pingcap.com/tidb/stable/release-5.3.3.md): TiDB 5.3.3 was released on September 14, 2022. The bug fix in TiKV addresses continuous SQL execution errors in the cluster after PD leader switch or PD restart. The issue was caused by a TiKV bug that has been fixed in v5.3.3. Affected versions include v5.3.2 and v5.4.2. Upgrading to v5.3.3 or restarting TiKV nodes can resolve the issue. For more details, refer to issue #12934 on GitHub. - [5.3.2](https://docs.pingcap.com/tidb/stable/release-5.3.2.md): TiDB 5.3.2 was released on June 29, 2022. It is not recommended to use this version due to a known bug, which has been fixed in v5.3.3. The release includes compatibility changes, improvements, and bug fixes for TiDB, PD, TiKV, TiFlash, and various tools like TiDB Data Migration, TiDB Lightning, Backup & Restore, TiCDC, and TiDB Data Migration. - [5.3.1](https://docs.pingcap.com/tidb/stable/release-5.3.1.md): TiDB 5.3.1 was released on March 3, 2022. The release includes compatibility changes, improvements, and bug fixes for TiDB, TiKV, PD, TiCDC, TiFlash, Backup & Restore (BR), and TiDB Data Migration (DM). Some notable changes include optimizing user login mode mapping, reducing TiCDC recovery time, and fixing various bugs in TiDB, TiKV, PD, TiFlash, and tools like TiCDC and TiDB Lightning. These fixes address issues related to data import, user login, garbage collection, configuration parameters, and more. - [5.3.0](https://docs.pingcap.com/tidb/stable/release-5.3.0.md): TiDB 5.3.0 introduces temporary tables, table attributes, and user privileges on TiDB Dashboard for improved performance and security. It also enhances TiDB Data Migration, supports parallel import using multiple TiDB Lightning instances, and continuous profiling for better observability. Compatibility changes and configuration file parameters have been modified. The release also includes new SQL features, security enhancements, stability improvements, and diagnostic efficiency. Additionally, bug fixes and improvements have been made to TiDB, TiKV, PD, TiFlash, and TiCDC. The cyclic replication feature between TiDB clusters has been removed. Telemetry now includes information about the usage of the TEMPORARY TABLE feature. - v5.2 - [5.2.4](https://docs.pingcap.com/tidb/stable/release-5.2.4.md): Learn about the new features, compatibility changes, improvements, and bug fixes in TiDB 5.2.4. - [5.2.3](https://docs.pingcap.com/tidb/stable/release-5.2.3.md): TiDB 5.2.3 was released on December 3, 2021. This version includes a bug fix for TiKV, addressing an issue where the `GcKeys` task does not work when called by multiple keys, leading to potential problems with compaction filter GC. (#11217) - [5.2.2](https://docs.pingcap.com/tidb/stable/release-5.2.2.md): TiDB 5.2.2 was released on October 29, 2021. The release includes various improvements and bug fixes for TiDB, TiKV, PD, TiCDC, TiFlash, and TiDB Binlog. Improvements include showing affected SQL statements in debug logs, support for showing backup and restore data size, and more. Bug fixes address issues such as plan-cache detection, wrong partition pruning, and various other issues related to query functions, client connections, and data replication. - [5.2.1](https://docs.pingcap.com/tidb/stable/release-5.2.1.md): TiDB 5.2.1 was released on September 9, 2021. Bug fixes include resolving an error in TiDB caused by a wrong execution plan and fixing the issue of unavailable TiKV caused by Raftstore deadlock when migrating Regions. - [5.2.0](https://docs.pingcap.com/tidb/stable/release-5.2.0.md): TiDB 5.2.0 introduces new features and improvements, including support for expression indexes, Lock View GA, TiFlash I/O traffic limit, and more. Compatibility changes include new system variables and configuration file parameters. The release also includes bug fixes and feature enhancements for TiDB, TiKV, TiFlash, and tools like TiCDC, BR, Lightning, and Dumpling. - v5.1 - [5.1.5](https://docs.pingcap.com/tidb/stable/release-5.1.5.md): TiDB 5.1.5 was released on December 28, 2022. The release includes compatibility changes and numerous bug fixes for TiDB, TiKV, PD, TiFlash, and various tools. Bug fixes address issues such as panics, wrong results, and incorrect behaviors. Fixes also include issues related to data loss, memory usage, and incorrect metrics. - [5.1.4](https://docs.pingcap.com/tidb/stable/release-5.1.4.md): TiDB 5.1.4 Release Notes: Compatibility changes include default value changes for system variables. Improvements in partition pruning, memory usage tracking, and speed of inserting SST files. Bug fixes address memory leaks, configuration issues, and incorrect query results. Tools like TiCDC and TiFlash also receive various fixes and improvements. - [5.1.3](https://docs.pingcap.com/tidb/stable/release-5.1.3.md): TiDB 5.1.3 was released on December 3, 2021. This version includes a bug fix for TiKV, addressing an issue where the `GcKeys` task does not work when called by multiple keys, leading to potential problems with compaction filter GC. - [5.1.2](https://docs.pingcap.com/tidb/stable/release-5.1.2.md): TiDB 5.1.2 was released on September 27, 2021. The release includes compatibility changes, improvements, bug fixes, and updates to various tools such as TiCDC, TiKV, PD, TiFlash, BR, Dumpling, and TiCDC. The release addresses numerous bug fixes and improvements to enhance performance and stability. - [5.1.1](https://docs.pingcap.com/tidb/stable/release-5.1.1.md): TiDB 5.1.1 was released on July 30, 2021. The release includes compatibility changes, feature enhancements, improvements, bug fixes, and updates to TiDB Dashboard, TiFlash, TiKV, and various tools. Notable changes include default value changes for variables, support for OIDC SSO in TiDB Dashboard, and bug fixes for data loss and panic issues. - [5.1.0](https://docs.pingcap.com/tidb/stable/release-5.1.0.md): TiDB 5.1 introduces support for Common Table Expression, dynamic privilege feature, and Stale Read. It also includes new statistics type, Lock View feature, and TiKV write rate limiter. Compatibility changes include new system and configuration variables. Other improvements and bug fixes are also part of this release. - v5.0 - [5.0.6](https://docs.pingcap.com/tidb/stable/release-5.0.6.md): TiDB 5.0.6 was released on December 31, 2021. The release includes compatibility changes, improvements, bug fixes, and updates to various tools such as TiCDC, TiKV, PD, TiDB Lightning, TiFlash, Backup & Restore (BR), and Dumpling. The changes include enhancements to error handling, performance improvements, bug fixes related to SQL statements, and various optimizations for different tools. - [5.0.5](https://docs.pingcap.com/tidb/stable/release-5.0.5.md): TiDB 5.0.5 was released on December 3, 2021. The bug fix for TiKV addresses an issue where the `GcKeys` task does not work when called by multiple keys, causing compaction filter GC to not drop MVCC deletion information. Issue #11217 on GitHub provides more details. - [5.0.4](https://docs.pingcap.com/tidb/stable/release-5.0.4.md): Compatibility changes include fixes for slow `SHOW VARIABLES` execution, default value change for `tidb_stmt_summary_max_stmt_count`, and bug fixes that may cause upgrade incompatibilities. Feature enhancements include support for setting `tidb_enforce_mpp=1` and dynamic TiCDC configurations. Improvements cover auto-analyze trigger, MPP query retry support, and stable result mode. Bug fixes address various issues in TiDB, TiKV, PD, TiFlash, and tools like Dumpling and TiCDC. - [5.0.3](https://docs.pingcap.com/tidb/stable/release-5.0.3.md): TiDB 5.0.3 was released on July 2, 2021. The release includes compatibility changes, feature enhancements, improvements, bug fixes, and updates for TiDB, TiKV, PD, TiFlash, and Tools like TiCDC, Backup & Restore (BR), and TiDB Lightning. Some notable changes include support for pushing down operators and functions to TiFlash, memory consumption limits for TiCDC, and bug fixes for various issues in TiDB, TiKV, PD, and TiFlash. - [5.0.2](https://docs.pingcap.com/tidb/stable/release-5.0.2.md): TiDB 5.0.2 was released on June 10, 2021. The new version includes compatibility changes, new features, improvements, bug fixes, and updates to various tools such as TiKV, TiFlash, PD, TiCDC, Backup & Restore (BR), and TiDB Lightning. Some notable changes include the deprecation of `--sort-dir` in TiCDC, enabling the Hibernate Region feature in TiKV, and various bug fixes in TiDB, TiKV, PD, TiFlash, and tools like TiCDC, BR, and TiDB Lightning. - [5.0.1](https://docs.pingcap.com/tidb/stable/release-5.0.1.md): TiDB 5.0.1 was released on April 24, 2021. The default value of `committer-concurrency` changed to 128. Various bug fixes and improvements were made to TiDB, TiKV, PD, TiFlash, and Tools. For example, TiDB fixed issues with query results and performance regression, while TiKV fixed issues with coprocessors and startup failures. Tools like TiDB Lightning and Backup & Restore also received bug fixes. - [5.0 GA](https://docs.pingcap.com/tidb/stable/release-5.0.0.md): TiDB 5.0 introduces MPP architecture, clustered index, async commit, and stability improvements. It also enhances compatibility changes, configuration parameters, and new features. Additionally, it optimizes performance, high availability, disaster recovery, data migration, diagnostics, deployment, and maintenance. Telemetry is added for cluster usage metrics. - [5.0.0-rc](https://docs.pingcap.com/tidb/stable/release-5.0.0-rc.md): TiDB v5.0.0-rc is the predecessor version of TiDB v5.0. It includes new features like clustered index, async commit, reduced jitters, Raft Joint Consensus algorithm, optimized `EXPLAIN` features, invisible index, and improved reliability for enterprise data. It also supports desensitizing error messages and log files for security. Performance improvements include async commit, optimizer stability, and reduced performance jitter. It also enhances system availability during Region membership change. Additionally, it supports backup and restore to AWS S3 and Google Cloud GCS, data import/export, and optimized `EXPLAIN` features for troubleshooting SQL performance issues. Deployment and maintenance improvements include enhanced `mirror` command and easier installation process. - v4.0 - [4.0.16](https://docs.pingcap.com/tidb/stable/release-4.0.16.md): TiDB 4.0.16 was released on December 17, 2021. The release includes compatibility changes for TiKV and Tools, improvements for TiDB, TiKV, and Tools, bug fixes for TiDB, TiKV, PD, TiFlash, TiDB Binlog, and TiCDC. The bug fixes address various issues such as query panics, wrong results, panics, and memory leaks. The release also includes fixes for TiCDC replication interruption, OOM in container environments, and memory leak issues. - [4.0.15](https://docs.pingcap.com/tidb/stable/release-4.0.15.md): TiDB 4.0.15 Release Notes: Compatibility changes include bug fixes that might cause upgrade incompatibilities. Feature enhancements for TiKV support changing configurations dynamically. Improvements for TiDB, TiKV, PD, and Tools. Bug fixes for TiDB, TiKV, PD, TiFlash, Backup & Restore, and TiCDC. - [4.0.14](https://docs.pingcap.com/tidb/stable/release-4.0.14.md): TiDB 4.0.14 was released on July 27, 2021. The release includes compatibility changes, feature enhancements, improvements, bug fixes, and updates to various tools. Some notable changes include default value updates for TiDB and TiKV, support for OIDC SSO in TiDB Dashboard, and bug fixes for TiDB, TiKV, PD, TiFlash, and various tools. - [4.0.13](https://docs.pingcap.com/tidb/stable/release-4.0.13.md): TiDB 4.0.13 was released on May 28, 2021. New features include support for changing `AUTO_INCREMENT` to `AUTO_RANDOM` and the addition of `infoschema.client_errors_summary` tables. Improvements were made to TiDB, TiKV, PD, TiFlash, and Tools. Bug fixes were also implemented for TiDB, TiKV, TiFlash, and Tools, addressing various issues such as query results, panics, and memory usage. - [4.0.12](https://docs.pingcap.com/tidb/stable/release-4.0.12.md): TiDB 4.0.12 was released on April 2, 2021. New features include tools to check the status of `tiflash replica` for online rolling updates. Improvements were made to TiDB, TiKV, PD, TiFlash, and various tools. Bug fixes were also implemented for TiDB, TiKV, PD, TiFlash, TiCDC, Backup & Restore, and TiDB Lightning. - [4.0.11](https://docs.pingcap.com/tidb/stable/release-4.0.11.md): TiDB 4.0.11 was released on February 26, 2021. New features include support for `utf8_unicode_ci` and `utf8mb4_unicode_ci` collations. Improvements were made to inner joins, Grafana dashboards, and slow query metrics. Bug fixes address issues with collation, type inference, and function errors. TiKV improvements include support for multiple clusters in Grafana dashboards and bug fixes for memory diagnostics and OOM errors. PD fixes member health metrics and store limit persistence issues. TiFlash bug fixes address decimal type results, data loss, and crash issues. Tools like TiCDC, BR, and TiDB Lightning also received bug fixes and improvements. - [4.0.10](https://docs.pingcap.com/tidb/stable/release-4.0.10.md): TiDB 4.0.10 was released on January 15, 2021. New features include redacting user data from logs and configurable size limits for key-value entries. Bug fixes address concurrency issues, duplicate bindings, and incorrect results. Improvements include optimized metrics and upgraded dependencies. Various tools have also been updated and fixed, such as TiCDC, Dumpling, Backup & Restore, TiDB Binlog, and TiDB Lightning. - [4.0.9](https://docs.pingcap.com/tidb/stable/release-4.0.9.md): TiDB 4.0.9 was released on December 21, 2020. The release includes compatibility changes, new features, improvements, bug fixes, and updates to TiKV, TiDB Dashboard, PD, TiFlash, and various tools. Notable changes include the deprecation of the `enable-streaming` configuration item in TiDB, support for storing the latest data of the storage engine on multiple disks in TiFlash, and various bug fixes in TiDB and TiKV. - [4.0.8](https://docs.pingcap.com/tidb/stable/release-4.0.8.md): TiDB 4.0.8 was released on October 30, 2020. New features include support for the new aggregate function `APPROX_PERCENTILE` and pushing down `CAST` functions in TiFlash. Improvements were made to TiDB, TiKV, PD, and TiFlash. Bug fixes were also implemented for TiDB, TiKV, PD, TiFlash, Backup and Restore (BR), TiCDC, and TiDB Lightning. - [4.0.7](https://docs.pingcap.com/tidb/stable/release-4.0.7.md): TiDB 4.0.7 was released on September 29, 2020. New features include the addition of the `GetAllMembers` function in the PD client and support for generating the metrics relationship graph in TiDB Dashboard. Improvements were made to TiDB, TiKV, PD, TiFlash, and various tools. Bug fixes were also implemented for TiDB, TiKV, PD, TiFlash, and tools like Backup & Restore and Dumpling. - [4.0.6](https://docs.pingcap.com/tidb/stable/release-4.0.6.md): TiDB 4.0.6 was released on September 15, 2020. New features include TiFlash support for outer join and TiDB Dashboard improvements. Tools like TiCDC and TiKV have also been updated. Bug fixes for TiDB, TiKV, PD, TiFlash, and various tools are included in this release. - [4.0.5](https://docs.pingcap.com/tidb/stable/release-4.0.5.md): TiDB 4.0.5 was released on August 31, 2020. The new version includes compatibility changes, new features, improvements, bug fixes, and updates to TiKV, TiFlash, Tools, PD, and TiDB Lightning. Some notable changes include support for the unified log format with TiDB, optimization of performance, bug fixes for various issues, and support for encryption at rest for data storage in TiFlash. - [4.0.4](https://docs.pingcap.com/tidb/stable/release-4.0.4.md): TiDB 4.0.4 was released on July 31, 2020. Bug fixes include issues with querying `information_schema.columns`, errors with `PointGet` and `BatchPointGet` operators, wrong results with `BatchPointGet`, and incorrect query results with the `HashJoin` operator encountering `set` or `enum` type. - [4.0.3](https://docs.pingcap.com/tidb/stable/release-4.0.3.md): TiDB 4.0.3 was released on July 24, 2020. New features include TiDB Dashboard improvements, TiFlash file encryption, and support for various tools. Improvements were made to TiDB, TiKV, PD, and TiDB Dashboard. Bug fixes were also implemented for TiDB, TiKV, PD, TiDB Dashboard, TiFlash, TiCDC, Backup & Restore, Dumpling, TiDB Lightning, and TiDB Binlog. - [4.0.2](https://docs.pingcap.com/tidb/stable/release-4.0.2.md): TiDB 4.0.2 was released on July 1, 2020. The new version includes compatibility changes, new features, improvements, bug fixes, and new changes. Some highlights include support for new aggregate functions, improvements in query latency, and bug fixes related to execution plan, runtime errors, and data replication. Additionally, there are new features and improvements in TiKV, PD, TiFlash, and Tools. - [4.0.1](https://docs.pingcap.com/tidb/stable/release-4.0.1.md): TiDB 4.0.1 was released on June 12, 2020. New features include support for custom timeout for PD client and new collation framework in TiFlash. Bug fixes address issues with configuration, monitoring metrics, and store information retrieval. Backup & Restore (BR) now includes a version check to avoid compatibility issues. - [4.0 GA](https://docs.pingcap.com/tidb/stable/release-4.0-ga.md): TiDB 4.0.0 GA was released on May 28, 2020. This version optimized error messages for large-sized transactions, improved usability of `Changefeed` configuration file, added new configuration items and support for various syntax and functions, fixed multiple bugs and issues in TiKV, TiFlash, PD, and Tools, added new monitoring items and support for various features in PD, and fixed various issues in Backup & Restore (BR) and TiCDC. - [4.0.0-rc.2](https://docs.pingcap.com/tidb/stable/release-4.0.0-rc.2.md): TiDB 4.0 RC.2 was released on May 15, 2020. The release includes compatibility changes, important bug fixes, new features, and bug fixes for TiDB, TiKV, PD, TiFlash, and various tools. Some notable changes include the removal of the size limit for a single transaction when TiDB Binlog is enabled, support for the BACKUP and RESTORE commands, and the addition of encryption-related monitoring metrics in Grafana dashboard. Additionally, there are numerous bug fixes for issues such as wrong partition selection, incorrect index range building, and performance reduction. The release also introduces new features like support for the auto_random option in the CREATE TABLE statement and the ability to manage replication tasks using cdc cli. - [4.0.0-rc.1](https://docs.pingcap.com/tidb/stable/release-4.0.0-rc.1.md): TiDB 4.0 RC.1 was released on April 28, 2020. The release includes compatibility changes, important bug fixes, new features, and bug fixes for TiKV, TiDB, TiFlash, TiCDC, Backup & Restore (BR), and Placement Driver (PD). The bug fixes address issues such as data inconsistency, deadlock, and replication failure. New features include support for sending Coprocessor requests to TiFlash in batches and enabling the load-based split region operation. Additionally, TiFlash now supports pushing down the fromUnixTime and dateFormat functions. - [4.0.0-rc](https://docs.pingcap.com/tidb/stable/release-4.0.0-rc.md): TiDB 4.0 RC released on April 8, 2020. It includes compatibility changes, bug fixes, new features, and tools. TiKV supports the `pipelined` feature in pessimistic transactions, improving TPC-C performance by 20%. TiDB adds case-insensitive collation and enhances the `RECOVER TABLE` syntax. TiKV now supports TLS in the HTTP port. PD supports getting default PD configuration information through the HTTP API. Bug fixes include issues with replication, subquery results, and DDL job internal retry. Tools like TiDB Lightning and TiCDC also have bug fixes and new features. - [4.0.0-beta.2](https://docs.pingcap.com/tidb/stable/release-4.0.0-beta.2.md): TiDB 4.0.0 Beta.2 was released on March 18, 2020. The new features include support for persisting dynamically updated configurations, bidirectional data replication, TLS configuration, change data capture, and experimental features like incremental backup. Bug fixes address issues with panic, hibernate regions, replication delay, and compatibility. TiDB Ansible now supports injecting node information to etcd and deploying services on the ARM platform. - [4.0.0-beta.1](https://docs.pingcap.com/tidb/stable/release-4.0.0-beta.1.md): TiDB 4.0.0 Beta.1 was released on February 28, 2020. It includes compatibility changes, new features, and bug fixes. Some highlights include support for SQL performance diagnosis, the `Sequence` function, and TLS support between components. Additionally, TiDB Lightning now has a bug fix for the web interface. - [4.0.0-beta](https://docs.pingcap.com/tidb/stable/release-4.0.0-beta.md): TiDB version 4.0.0-beta and TiDB Ansible version 4.0.0-beta were released on January 17, 2020. The release includes various improvements such as increased accuracy in calculating the cost of Index Join, support for Table Locks, and optimization of the error code of SQL error messages. TiKV was also upgraded to RocksDB version 6.4.6 and now supports quick backup and restoration. PD now supports optimizing hotspot scheduling and adding Placement Rules feature. TiDB Lightning added a parameter to set the password of the downstream database, and TiDB Ansible now supports deploying and maintaining TiFlash. - v3.1 - [3.1.2](https://docs.pingcap.com/tidb/stable/release-3.1.2.md): TiDB 3.1.2 was released on June 4, 2020. Bug fixes include error handling during backup and restoration with S3 and GCS, and a `DefaultNotFound` error during restoration. Tools like Backup & Restore (BR) now automatically retry on poor network, fix restoration failures, data loss issues, and support AWS KMS for server-side encryption with S3 storage. - [3.1.1](https://docs.pingcap.com/tidb/stable/release-3.1.1.md): TiDB 3.1.1 was released on April 30, 2020. New features include table option for `auto_rand_base` and `Feature ID` comment. Bug fixes include isolation read setting, partition selection syntax, and wrong results from nested queries. TiFlash also received bug fixes and improvements in data reading and storage path modification. Backup & Restore (BR) fixed issues related to table restoration and data insertion. - [3.1.0 GA](https://docs.pingcap.com/tidb/stable/release-3.1.0-ga.md): TiDB 3.1.0 GA was released on April 16, 2020. It includes compatibility changes, new features, bug fixes, and improvements for TiDB, TiFlash, TiKV, and tools like Backup & Restore and TiDB Binlog. Notable changes include support for displaying Coprocessor tasks, optimizing hot Region scheduling, and fixing various panic and data loss issues. The release also includes improvements to TiDB Ansible for better monitoring and configuration parameters. - [3.1.0-rc](https://docs.pingcap.com/tidb/stable/release-3.1.0-rc.md): TiDB 3.1 RC was released on April 2, 2020. It includes new features such as improved partition pruning, support for `RECOVER` syntax, and TLS certificate updates. Bug fixes include resolving issues with TiFlash replica, `last_insert_id`, and `Aggregation` pushdown. TiKV now supports TLS authentication and AWS IAM web identity for backup. PD has fixed data race issues and placement rule inconsistencies. Tools like TiDB Lightning and BR have also been optimized and fixed. - [3.1.0-beta.2](https://docs.pingcap.com/tidb/stable/release-3.1.0-beta.2.md): TiDB 3.1 Beta.2 was released on March 9, 2020. It includes compatibility changes, new features, bug fixes, and improvements for TiDB, TiKV, PD Client, Backup, PD, TiFlash, and TiDB Ansible. Some known issues are fixed in new versions, so it is recommended to use the latest 3.1.x version. - [3.1.0-beta.1](https://docs.pingcap.com/tidb/stable/release-3.1.0-beta.1.md): TiDB 3.1 Beta.1 was released on January 10, 2020. The release includes changes to TiKV, such as renaming backup files and adding incremental backup features. Tools like BR have improved backup progress information and added features for partitioned tables. TiDB Ansible now automatically disables Transparent Huge Pages and adds Grafana monitoring for BR components. Overall, the release focuses on improving backup and restore processes, monitoring, and deployment optimization. - [3.1.0-beta](https://docs.pingcap.com/tidb/stable/release-3.1.0-beta.md): TiDB 3.1 Beta was released on December 20, 2019. It includes SQL Optimizer improvements and supports the Follower Read feature. TiKV now supports distributed backup and restore, as well as the Follower Read feature. PD also supports distributed backup and restore. - v3.0 - [3.0.20](https://docs.pingcap.com/tidb/stable/release-3.0.20.md): TiDB 3.0.20 was released on December 25, 2020. The release includes compatibility changes, improvements, and bug fixes for TiDB, TiKV, and PD. Some notable bug fixes include addressing issues with incorrect cache of transaction status, inaccurate statistics, and stack overflow. - [3.0.19](https://docs.pingcap.com/tidb/stable/release-3.0.19.md): TiDB 3.0.19 was released on September 25, 2020. Compatibility changes include import path and copyright information updates. Improvements were made to mitigate failure recovery impact, support concurrency adjustment, and set nonadjustable values. Bug fixes were made for query errors, privilege checks, type changes, constraint checks, table lock release, operator handling, and panic parsing. Tools like TiDB Lightning also received fixes for process exit timing. - [3.0.18](https://docs.pingcap.com/tidb/stable/release-3.0.18.md): TiDB 3.0.18 was released on August 21, 2020. The release includes improvements to TiDB Binlog and bug fixes for TiDB and TiKV. Bug fixes for TiDB include issues with handling decimal, set, and enum types, as well as problems with duplicate keys and cached execution plans. TiKV's bug fix involves changing the GC failure log level. TiDB Lightning also received fixes for issues with the log file argument, syntax errors, and unexpected calls. - [3.0.17](https://docs.pingcap.com/tidb/stable/release-3.0.17.md): TiDB 3.0.17 was released on Aug 3, 2020. The release includes improvements such as decreasing the default value of the query-feedback-limit configuration item and bug fixes like returning the actual error message instead of an empty set. TiKV also added the hibernate-timeout configuration to improve rolling update performance. TiDB Lightning deprecated the black-white-list filter format and fixed the issue of the log-file flag being ignored. - [3.0.16](https://docs.pingcap.com/tidb/stable/release-3.0.16.md): TiDB 3.0.16 was released on July 03, 2020. The release includes improvements such as support for 'is null' filter condition, handling of SQL timeout issues, and removal of sensitive information in slow query logs. Bug fixes include resolving data inconsistency issues, fixing panic issues, and addressing errors in JSON comparison and query results. TiKV and PD also received bug fixes for issues related to store heartbeats, peer removal, and error handling. - [3.0.15](https://docs.pingcap.com/tidb/stable/release-3.0.15.md): TiDB 3.0.15 was released on June 5, 2020. New features include support for admin recover index and admin check index statements on partitioned tables, as well as optimization of memory allocation mechanism. Bug fixes address issues such as incorrect results in PointGet and inconsistent results between TiDB and MySQL when XOR operates on a floating-point number. TiKV fixes issues related to memory defragmentation and gRPC disconnection. - [3.0.14](https://docs.pingcap.com/tidb/stable/release-3.0.14.md): TiDB 3.0.14 was released on May 9, 2020. The release includes compatibility changes, important bug fixes, new features, bug fixes, and improvements for TiDB, TiKV, and Tools. Some of the bug fixes include issues with query results, panic occurrences, and incorrect behavior. New features include enhanced syntax support and improved performance. - [3.0.13](https://docs.pingcap.com/tidb/stable/release-3.0.13.md): TiDB 3.0.13 was released on April 22, 2020. The bug fixes include resolving issues with the `INSERT ... ON DUPLICATE KEY UPDATE` statement and fixing the system getting stuck and becoming unavailable during `Region Merge` in TiKV. - [3.0.12](https://docs.pingcap.com/tidb/stable/release-3.0.12.md): TiDB 3.0.12 was released on March 16, 2020. It includes compatibility changes, new features, bug fixes, and improvements for TiDB, TiKV, PD, and TiDB Ansible. Some known issues are fixed in new versions, so it is recommended to use the latest 3.0.x version. New features include dynamic loading of replaced certificate files, flow limiting for DDL requests, and support for exiting the TiDB server when binlog write fails. Bug fixes address issues with locking, error message display, decimal point accuracy, and data index inconsistency. Additionally, improvements have been made to TiKV's flow control mechanism and PD's Region information processing. - [3.0.11](https://docs.pingcap.com/tidb/stable/release-3.0.11.md): TiDB 3.0.11 was released on March 4, 2020. It includes compatibility changes, new features, bug fixes, and updates for TiDB, TiDB Binlog, TiDB Lightning, TiKV, and TiDB Ansible. Some known issues are fixed in new versions, so it is recommended to use the latest 3.0.x version. - [3.0.10](https://docs.pingcap.com/tidb/stable/release-3.0.10.md): TiDB 3.0.10 was released on February 20, 2020. It includes various bug fixes and improvements for TiDB, TiKV, PD, and TiDB Ansible. Some notable fixes include wrong Join results, data visibility issues, and system panic problems. TiDB Ansible also added new monitoring items to the dashboard. The release notes recommend using the latest 3.0.x version due to known issues in this release. - [3.0.9](https://docs.pingcap.com/tidb/stable/release-3.0.9.md): TiDB 3.0.9 was released on January 14, 2020. It includes fixes for known issues and new features. Some improvements were made to Executor, Server, DDL, Planner, TiKV, PD, Tools, and TiDB Ansible. Notable changes include support for system variables, monitoring metrics, and optimizations for transaction execution latency. Additionally, support for using backlash in the location label name and automatically creating directories for TiDB Lightning deployment was added. - [3.0.8](https://docs.pingcap.com/tidb/stable/release-3.0.8.md): TiDB 3.0.8 was released on December 31, 2019. It includes various fixes and improvements for SQL optimizer, SQL execution engine, DDL, server, transaction, monitor, TiKV, PD, and TiDB Ansible. Notable changes include SQL binding plan fixes, error message optimizations, and support for certificate-based authentication. The default value of `tidb_txn_mode` variable is updated to `"pessimistic"`. PD also received performance optimizations and bug fixes. TiDB Ansible saw various logic optimizations and upgrades. - [3.0.7](https://docs.pingcap.com/tidb/stable/release-3.0.7.md): TiDB 3.0.7 was released on December 4, 2019. It includes fixes for issues related to lock TTL, timezone parsing, result accuracy, data precision, and statistics accuracy. TiKV also received updates to improve deadlock detection and fix a memory leak issue. - [3.0.6](https://docs.pingcap.com/tidb/stable/release-3.0.6.md): TiDB 3.0.6 was released on November 28, 2019, with various fixes and optimizations. The release includes improvements to the SQL optimizer, SQL execution engine, server, DDL, TiKV, PD, TiDB Binlog, and TiDB Lightning. Fixes include issues with window function AST, pushing down `STREAM AGG()`, handling quotes for SQL binding, and more. TiKV improvements include accurate `lock_manager`, support for `innodb_lock_wait_timeout`, and dynamic modification of the GC I/O limit using `tikv-ctl`. PD enhancements include lower client log level and warning log for generating a timestamp. TiDB Binlog and TiDB Lightning also received fixes and improvements. - [3.0.5](https://docs.pingcap.com/tidb/stable/release-3.0.5.md): TiDB 3.0.5 was released on October 25, 2019, with various improvements and bug fixes. The release includes enhancements to the SQL optimizer, SQL execution engine, server, DDL, monitor, TiKV, PD, TiDB Binlog, TiDB Lightning, and TiDB Ansible. Improvements include support for boundary checking on Window Functions, fixing issues with index join and outer join, and adding monitoring metrics for various operations. Additionally, TiKV received storage and performance optimizations, while PD saw improvements in storage precision and HTTP request handling. TiDB Ansible also received updates to monitoring metrics and configuration file simplification. - [3.0.4](https://docs.pingcap.com/tidb/stable/release-3.0.4.md): TiDB 3.0.4 was released on October 8, 2019, with new features including system table for troubleshooting SQL performance issues, improvements in split performance and reverse scan, and fixed issues related to slow query logs and data replication. The release also includes contributions from the community and updates to TiDB, TiKV, PD, and TiDB Ansible. - [3.0.3](https://docs.pingcap.com/tidb/stable/release-3.0.3.md): TiDB 3.0.3 was released on August 29, 2019. It includes various fixes and updates for SQL optimizer, SQL execution engine, server, DDL, monitor, TiKV, PD, TiDB Binlog, TiDB Lightning, and TiDB Ansible. Notable fixes include issues with incorrect results, type errors, panic occurrences, and permission check errors. The release also optimizes PD operations, removes unsupported Grafana Collector components, and updates TiKV alerting rules. Additionally, TiDB Ansible now supports Spark V2.4.3 and TiSpark V2.1.4. - [3.0.2](https://docs.pingcap.com/tidb/stable/release-3.0.2.md): TiDB 3.0.2 was released on August 7, 2019, with various fixes and improvements. The release includes fixes for SQL optimizer, SQL execution engine, server, DDL, monitor, TiKV, PD, TiDB Binlog, TiDB Lightning, and TiDB Ansible. Fixes include issues with query plans, query results, error messages, and performance optimizations. - [3.0.1](https://docs.pingcap.com/tidb/stable/release-3.0.1.md): TiDB 3.0.1 Release Notes July 16, 2019. TiDB version 3.0.1. Add support for MAX_EXECUTION_TIME feature. Support auto-adjustment of incremental gap for auto-increment IDs. Add ADMIN PLUGINS ENABLE/DISABLE SQL statement. Prohibit Window Functions from being cached in Prepare Plan Cache. Fix various bugs and issues. TiKV: Add statistics of blob file size. Fix core dump issue. PD: Add enable-grpc-gateway configuration option. Optimize hot Region scheduling strategy. Tools: TiDB Binlog - Optimize Pump GC strategy. TiDB Lightning - Fix import error. TiDB Ansible - Add precheck feature, update monitoring information. - [3.0 GA](https://docs.pingcap.com/tidb/stable/release-3.0-ga.md): TiDB 3.0 GA was released on June 28, 2019, with improved stability, usability, and performance. New features include Window Functions, Views, partitioned tables, and the plugin framework. The SQL Optimizer has been optimized for better performance, and DDL now supports fast recovery of mistakenly deleted tables. TiKV now supports distributed GC, multi-thread Raftstore, and batch receiving and sending Raft messages. Tools like TiDB Lightning and TiDB Binlog have also been enhanced with new features and performance improvements. The TiDB Ansible has been upgraded to support deployment and operations for TiDB Lightning, and to optimize monitoring components. - [3.0.0-rc.3](https://docs.pingcap.com/tidb/stable/release-3.0.0-rc.3.md): TiDB 3.0.0-rc.3 was released on June 21, 2019, with improvements in stability, usability, features, SQL optimizer, statistics, and execution engine. Fixes and new features were added to TiDB, PD, TiKV, and TiDB Ansible. Notable improvements include automatic loading statistics, manual splitting of table and index regions, and support for pessimistic transactions in TiKV. - [3.0.0-rc.2](https://docs.pingcap.com/tidb/stable/release-3.0.0-rc.2.md): TiDB 3.0.0-rc.2 was released on May 28, 2019, with improvements in stability, usability, features, SQL optimizer, statistics, and execution engine. The release includes enhancements to the SQL optimizer, execution engine, server, DDL, PD, TiKV, and tools like TiDB Binlog and TiDB Lightning. Some notable improvements include support for Index Join in more scenarios, handling virtual columns properly, and adding a metric to track data replication downstream. - [3.0.0-rc.1](https://docs.pingcap.com/tidb/stable/release-3.0.0-rc.1.md): TiDB 3.0.0-rc.1 was released on May 10, 2019, with improved stability, usability, features, SQL optimizer, statistics, and execution engine. The release includes enhancements to the SQL optimizer, execution engine, server, DDL, PD, TiKV, TiDB Binlog, Lightning, sync-diff-inspector, and TiDB Ansible. Notable improvements include support for SQL Plan Management, memory usage tracking, and control in the execution engine, and the addition of the `pre_split_regions` option for `CREATE TABLE` statements in DDL. The release also includes various bug fixes and performance optimizations. - [3.0.0-beta.1](https://docs.pingcap.com/tidb/stable/release-3.0.0-beta.1.md): TiDB 3.0.0 Beta.1 was released on March 26, 2019, with improved stability, usability, features, SQL optimizer, statistics, and execution engine. The release includes support for various SQL functions, privilege management, server enhancements, DDL improvements, and PD and TiKV optimizations. Tools like TiDB Binlog, Lightning, and data replication comparison tool have also been updated with new features and improvements. - [3.0.0-beta](https://docs.pingcap.com/tidb/stable/release-3.0-beta.md): TiDB 3.0 Beta, released on January 19, 2019, focuses on stability, SQL optimizer, statistics, and execution engine. New features include support for views, window functions, range partitioning, and hash partitioning. The SQL optimizer has been enhanced with various optimizations, including support for index join in transactions, constant propagation optimization, and support for subqueries in the DO statement. The SQL executor has also been optimized for better performance. Privilege management, server, compatibility, and DDL have all been improved. TiDB Lightning now supports batch import for a single table, while PD and TiKV have also received various enhancements and new features. - v2.1 - [2.1.19](https://docs.pingcap.com/tidb/stable/release-2.1.19.md): TiDB 2.1.19 was released on December 27, 2019. It includes various fixes and optimizations for SQL optimizer, SQL execution engine, server, DDL, TiKV, PD, and TiDB Ansible. Some notable fixes include resolving incorrect query results, memory overhead reduction, and fixing issues related to timezone, data duplication, and panic occurrences. The release also includes upgrades and optimizations for TiDB Binlog and TiDB Ansible. - [2.1.18](https://docs.pingcap.com/tidb/stable/release-2.1.18.md): TiDB 2.1.18 was released on November 4, 2019. The release includes various fixes and optimizations for SQL optimizer, SQL engine, server, DDL, monitor, and tools. Some notable improvements include support for using parameters in ORDER BY, GROUP BY, and LIMIT OFFSET, and adding new metrics for monitoring Add Index operation progress. The TiDB Ansible version 2.1.18 also includes updates and new monitoring items for TiDB Binlog. - [2.1.17](https://docs.pingcap.com/tidb/stable/release-2.1.17.md): TiDB 2.1.17 Release Notes: New features include `WHERE` clause in `SHOW TABLE REGIONS`, `config-check` feature in TiKV and PD, `remove-tombstone` command in pd-ctl, and `worker-count` and `txn-batch` configuration items in Reparo. Improvements in PD's scheduling process and TiKV's starting process. Changed behaviors in TiDB slow query logs and configuration files. Fixes and optimizations in SQL Optimizer, SQL Execution Engine, Server, DDL, Monitor, TiKV, PD, TiDB Binlog, TiDB Lightning, and TiDB Ansible. - [2.1.16](https://docs.pingcap.com/tidb/stable/release-2.1.16.md): TiDB 2.1.16 was released on August 15, 2019. It includes various fixes and improvements to the SQL optimizer, SQL execution engine, server, DDL, TiKV, TiDB Binlog, TiDB Lightning, and TiDB Ansible. Some notable changes include support for subqueries within SHOW statements, fixing issues with DATE_ADD function, and adding configuration items in Drainer for TiDB Binlog. - [2.1.15](https://docs.pingcap.com/tidb/stable/release-2.1.15.md): TiDB 2.1.15 was released on July 16, 2019. It includes various bug fixes and improvements, such as fixing issues with functions like DATE_ADD and INSERT, adding new SQL statements like SHOW TABLE REGIONS, and enhancing the Audit plugin. TiKV and PD also received updates to unify log formats and improve accuracy. Additionally, there were optimizations made to TiDB Binlog and TiDB Lightning, and new monitoring items added to TiDB Ansible. - [2.1.14](https://docs.pingcap.com/tidb/stable/release-2.1.14.md): TiDB 2.1.14 was released on July 04, 2019. It includes various bug fixes and improvements, such as fixing wrong query results, adding new system variables, optimizing memory usage, and adding new configuration items for TiDB Binlog and TiDB Ansible. Additionally, there are optimizations for TiKV and PD. - [2.1.13](https://docs.pingcap.com/tidb/stable/release-2.1.13.md): TiDB 2.1.13 was released on June 21, 2019. It includes features to scatter row IDs, optimize DDL metadata lifetime, fix OOM issue, update statistics, support Region presplit, improve MySQL compatibility, and fix estimation issues. TiKV fixes incomplete snapshots and adds a feature to check the validity of the block-size configuration. TiDB Binlog fixes wrong offset and adds advertise-addr configuration in Drainer. - [2.1.12](https://docs.pingcap.com/tidb/stable/release-2.1.12.md): TiDB 2.1.12 was released on June 13, 2019. It includes various bug fixes and improvements, such as fixing issues with data type mismatches, charset altering, and GRANT operations. The release also improves compatibility with MySQL and addresses issues with functions, data conversion, and error reporting. Additionally, PD and TiKV have also been updated to fix issues related to leader election and data availability during leader transfer and power failure. - [2.1.11](https://docs.pingcap.com/tidb/stable/release-2.1.11.md): TiDB 2.1.11 was released on June 03, 2019. It includes fixes for various issues in TiDB, PD, TiKV, and Tools. Some highlights are the fix for incorrect schema in delete from join, calculation errors of unix_timestamp(), and the addition of Drainer parameters in TiDB Ansible. - [2.1.10](https://docs.pingcap.com/tidb/stable/release-2.1.10.md): TiDB 2.1.10 was released on May 22, 2019, with various bug fixes and improvements. The release includes fixes for issues related to table schema, read results, generated columns, datetime functions, slow logs, and more. Additionally, improvements were made to TiKV and tools like TiDB Lightning and TiDB Binlog. The TiDB Ansible version 2.1.10 also received updates. - [2.1.9](https://docs.pingcap.com/tidb/stable/release-2.1.9.md): TiDB 2.1.9 was released on May 6, 2019. It includes various bug fixes and improvements, such as fixing compatibility issues, privilege check problems, and wrong result issues. The release also includes improvements to slow query logs and support for controlling the number of rows returned by operators. Additionally, there are updates to PD, TiKV, TiDB Binlog, TiDB Lightning, and sync-diff-inspector. TiDB Ansible has also been updated with documentation links and parameter removal. - [2.1.8](https://docs.pingcap.com/tidb/stable/release-2.1.8.md): TiDB 2.1.8 was released on April 12, 2019. It includes various bug fixes and improvements for TiDB, PD, TiKV, Tools, and TiDB Ansible. Some notable fixes include compatibility issues with MySQL, inaccurate statistics estimation, and performance improvements. The release also adds new configuration items and features for TiDB Binlog Pump and Drainer. Additionally, TiDB Ansible now has version limits for the operating system and rolling updates. - [2.1.7](https://docs.pingcap.com/tidb/stable/release-2.1.7.md): TiDB 2.1.7 was released on March 28, 2019. It includes various bug fixes, compatibility improvements, and new features such as support for subqueries in the `DO` statement, plugin framework, and checking binlog and Pump/Drainer status using SQL statements. PD also fixed an issue related to transferring leader step in balance-region. Additionally, the default retention time of Prometheus monitoring data in TiDB Ansible has been changed to 30d. - [2.1.6](https://docs.pingcap.com/tidb/stable/release-2.1.6.md): TiDB 2.1.6 and TiDB Ansible 2.1.6 were released on March 15, 2019. The release includes improvements in stability, SQL optimizer, statistics, and execution engine. Fixes and enhancements were made in SQL optimizer/executor, server, DDL, TiKV, and Tools. Notable changes include support for log_bin variable, sanity check for transactions, and fixing import failure due to non-alphanumeric characters in schema names. - [2.1.5](https://docs.pingcap.com/tidb/stable/release-2.1.5.md): TiDB 2.1.5 and TiDB Ansible 2.1.5 are released on February 28, 2019. The release improves stability, SQL optimizer, statistics, and execution engine. Fixes include issues with sorting, data overflow, and SQL query results. New features include system variables, HTTP API, and detailed error messages. PD now has an option to exclude Tombstone stores, and TiKV fixes issues with data import, errors, and panic caused by Region merge. Tools like Lightning and TiDB Binlog also receive updates. - [2.1.4](https://docs.pingcap.com/tidb/stable/release-2.1.4.md): TiDB 2.1.4 and TiDB Ansible 2.1.4 were released on February 15, 2019. The release includes improvements in stability, SQL optimizer, statistics, and execution engine. Fixes include issues with the SQL optimizer/executor, server, DDL, and TiKV. Lightning tool optimizations include memory usage, chunk separation removal, I/O concurrency limitation, batch data import support, and auto compactions in TiKV import mode. Additionally, support for disabling TiKV periodic Level-1 compaction parameter and limiting the number of import engines is added. Sync-diff-inspector now supports splitting chunks using TiDB statistics. - [2.1.3](https://docs.pingcap.com/tidb/stable/release-2.1.3.md): TiDB 2.1.3 and TiDB Ansible 2.1.3 are released with improvements in system stability, SQL optimizer, statistics, and execution engine. Fixes include issues with Prepared Plan Cache, Range computing, `CAST(str AS TIME(N))`, Generated Column, statistics histogram, `Sort Merge Join`, and more. Other improvements include support for Range for `_tidb_rowid` construction queries, `ALLOW_INVALID_DATES` SQL mode, and more. PD and TiKV also have fixes and improvements. TiDB Binlog fixes issues with the Pump client log and data inconsistency caused by unique key containing NULL value. - [2.1.2](https://docs.pingcap.com/tidb/stable/release-2.1.2.md): TiDB 2.1.2 and TiDB Ansible 2.1.2 were released on December 22, 2018. The release includes improvements in system compatibility and stability. Key updates include compatibility with TiDB Binlog of the Kafka version, improved exit mechanism during rolling updates, and fixes for various issues. PD and TiKV also received updates, such as fixing Region merge issues and support for configuration format in the unit of 'DAY'. Additionally, TiDB Lightning and TiDB Binlog were updated to support new features and eliminate bottlenecks. - [2.1.1](https://docs.pingcap.com/tidb/stable/release-2.1.1.md): TiDB 2.1.1 was released on December 12, 2018, with improvements in stability, SQL optimizer, statistics information, and execution engine. Fixes include round error of negative date, uncompress function data length check, and transaction retries. Default character set and collation of tables changed to utf8mb4. PD and TiKV also received various fixes and optimizations. Lightning tool optimized analyze mechanism and added support for storing checkpoint information locally. TiDB Binlog fixed output bug of pb files for tables with only primary key column. - [2.1 GA](https://docs.pingcap.com/tidb/stable/release-2.1-ga.md): TiDB 2.1 GA was released on November 30, 2018, with significant improvements in stability, performance, compatibility, and usability. The release includes optimizations in SQL optimizer, SQL executor, statistics, expressions, server, DDL, compatibility, Placement Driver (PD), TiKV, and tools. It also introduces TiDB Lightning for fast full data import. However, TiDB 2.1 does not support downgrading to v2.0.x or earlier due to the adoption of the new storage engine. Additionally, parallel DDL is enabled in TiDB 2.1, so clusters with TiDB version earlier than 2.0.1 cannot upgrade to 2.1 using rolling update. If upgrading from TiDB 2.0.6 or earlier to TiDB 2.1, ongoing DDL operations may slow down the upgrading process. - [2.1 RC5](https://docs.pingcap.com/tidb/stable/release-2.1-rc.5.md): TiDB 2.1 RC5 was released on November 12, 2018, with improvements in stability, SQL optimizer, statistics, and execution engine. Fixes include issues with IndexReader, IndexScan Prepared statement, Union statement, and JSON data conversion. Server improvements include log readability, table data retrieval, and environment variable additions. PD fixes issues related to Region key reading, `regions/check` API, PD restart join, and event loss. TiKV improves error messages, adds panic mark file, downgrades grpcio, and adds an upper limit to the `kv_scan` interface. - [2.1 RC4](https://docs.pingcap.com/tidb/stable/release-2.1-rc.4.md): TiDB 2.1 RC4 was released on October 23, 2018, with improvements in stability, SQL optimizer, statistics information, and execution engine. Fixes include issues with SQL optimizer, execution engine, statistics, server, compatibility, expressions, and DDL. PD fixes issues with tombstone TiKV, data race, PD server getting stuck, and leader switching. TiKV optimizes RocksDB Write stall issue, adds raftstore tick metrics, and upgrades RocksDB and grpcio. - [2.1 RC3](https://docs.pingcap.com/tidb/stable/release-2.1-rc.3.md): TiDB 2.1 RC3 was released on September 29, 2018, with improvements in stability, compatibility, SQL optimizer, and execution engine. The release includes fixes and enhancements for SQL optimizer, execution engine, server, compatibility, expressions, DML, DDL, and PD. TiKV also received performance optimizations, new features, and bug fixes. - [2.1 RC2](https://docs.pingcap.com/tidb/stable/release-2.1-rc.2.md): TiDB 2.1 RC2 was released on September 14, 2018, with improvements in stability, SQL optimizer, statistics, and execution engine. The release includes enhancements to SQL optimizer, SQL execution engine, statistics, server, compatibility, expressions, DML, DDL, TiKV Go Client, and Table Partition. PD features, improvements, and bug fixes are also included. TiKV performance, improvements, and bug fixes are part of the release as well. - [2.1 RC1](https://docs.pingcap.com/tidb/stable/release-2.1-rc.1.md): TiDB 2.1 RC1 was released on August 24, 2018, with improvements in stability, SQL optimizer, statistics, and execution engine. The release includes fixes for various issues in SQL optimizer and execution engine. PD introduces version control, rolling update, and region merge features. TiKV supports batch split and row-based region splitting for improved efficiency. Overall, the release focuses on performance optimization and bug fixes. - [2.1 Beta](https://docs.pingcap.com/tidb/stable/release-2.1-beta.md): TiDB 2.1 Beta release includes improvements in stability, SQL optimizer, statistics, and execution engine. It supports more MySQL syntax, decreases memory usage, and optimizes DDL and DML statements. PD enables Raft PreVote, optimizes scheduler issues, and adds metrics. TiKV upgrades Rust, adds metrics, and improves performance. Compatibility notes include not supporting rollback to v2.0.x and enabling raft learner by default in the new version. - v2.0 - [2.0.11](https://docs.pingcap.com/tidb/stable/release-2.0.11.md): TiDB 2.0.11 and TiDB Ansible 2.0.11 were released on January 3, 2019. The release includes improvements in system compatibility and stability. Fixes include handling errors when PD is in an abnormal condition, compatibility issues with MySQL, error message reporting, prefix index range, and panic issues with the `UPDATE` statement. TiKV also fixed two issues related to Region merge. - [2.0.10](https://docs.pingcap.com/tidb/stable/release-2.0.10.md): TiDB 2.0.10 and TiDB Ansible 2.0.10 were released on December 18, 2018. The release includes improvements in system compatibility and stability. Fixes include issues with DDL jobs, ORDER BY and UNION clauses, UNCOMPRESS function, ANSI_QUOTES SQL_MODE, select results, and more. PD fixes a possible RaftCluster deadlock issue, while TiKV optimizes leader transfer and fixes redundant Region heartbeats. - [2.0.9](https://docs.pingcap.com/tidb/stable/release-2.0.9.md): TiDB 2.0.9 was released on November 19, 2018, with significant improvements in system compatibility and stability. The release includes fixes for various issues, such as empty statistics histogram, panic issue with UNION ALL statement, stack overflow issue, and support for specifying utf8mb4 character set. PD and TiKV also received fixes for issues related to server startup failure and interface limits. - [2.0.8](https://docs.pingcap.com/tidb/stable/release-2.0.8.md): TiDB 2.0.8 was released on October 16, 2018, with improvements in system compatibility and stability. The release includes various bug fixes for TiDB and TiKV, addressing issues related to AUTO-ID, etcd session recovery, time zone handling, memory leaks, and join conversions. The TiKV bug fix resolves the increasing memory consumption by Raftstore EntryCache when a node goes down. - [2.0.7](https://docs.pingcap.com/tidb/stable/release-2.0.7.md): TiDB 2.0.7 was released on September 7, 2018, with improvements in system compatibility and stability. New features include the addition of the `PROCESSLIST` table in `information_schema`. Bug fixes address issues with index usage, join output, and query conditions. TiKV now opens the `dynamic-level-bytes` parameter by default to reduce space amplification, and updates approximate size and keys count after region merging. - [2.0.6](https://docs.pingcap.com/tidb/stable/release-2.0.6.md): TiDB 2.0.6 was released on August 6, 2018, with improvements in system compatibility and stability. The release includes various improvements and bug fixes for TiDB and TiKV. Some notable improvements include reducing transaction conflicts, improving row count estimation accuracy, and adding a recover mechanism for panics during the execution of `ANALYZE TABLE`. Bug fixes address issues such as incompatible `DROP USER` statement behavior, OOM errors for `INSERT`/`LOAD DATA` statements, and incorrect results for prefix index and `DECIMAL` operations. TiKV also sees improvements in scheduler slots, rollback transaction records, and RocksDB log file management, along with a fix for a crash issue during data type conversion. - [2.0.5](https://docs.pingcap.com/tidb/stable/release-2.0.5.md): TiDB 2.0.5 was released on July 6, 2018, with improvements in system compatibility and stability. New features include the `tidb_disable_txn_auto_retry` system variable. Bug fixes address issues with user login, data insertion, and command compatibility. PD and TiKV also received fixes for various issues. - [2.0.4](https://docs.pingcap.com/tidb/stable/release-2.0.4.md): TiDB 2.0.4 was released on June 15, 2018, with improvements in system compatibility and stability. It includes various enhancements and fixes for TiDB, PD, and TiKV. Some highlights for TiDB are support for `ALTER TABLE t DROP COLUMN a CASCADE` syntax, refining statement type display, and fixing issues related to data conversion and result order. PD now has improved behavior for the `max-pending-peer-count` argument, while TiKV includes the addition of the RocksDB `PerfContext` interface and fixes for slow `reverse-seek` and crash issues. - [2.0.3](https://docs.pingcap.com/tidb/stable/release-2.0.3.md): TiDB 2.0.3 was released on June 1, 2018, with improvements in system compatibility and stability. It includes various fixes and optimizations for TiDB, PD, and TiKV. Some highlights are support for modifying log level online, fixing issues with unique index and `ON DUPLICATE KEY UPDATE`, and addressing panic issues in specific conditions. - [2.0.2](https://docs.pingcap.com/tidb/stable/release-2.0.2.md): TiDB 2.0.2 was released on May 21, 2018, with improvements in system stability. The release includes fixes for Decimal division expression, support for `USE INDEX` syntax in `Delete` statement, and timeout mechanism for writing Binlog in TiDB. PD now filters disconnected nodes in balance leader scheduler, modifies transfer leader operator timeout, and fixes scheduling issues. TiKV fixes Raft log printing, supports configuring gRPC parameters, leader election timeout range, and resolves snapshot intermediate file deletion issue. - [2.0.1](https://docs.pingcap.com/tidb/stable/release-2.0.1.md): TiDB 2.0.1 was released on May 16, 2018, with improvements in MySQL compatibility and system stability. Updates include real-time progress for 'Add Index', a new session variable for automatic statistics update, bug fixes, compatibility improvements, and behavior changes. PD added a new scheduler, optimized region balancing, and fixed various issues. TiKV fixed issues related to reading, thread calls, raftstore blocking, and split causing dirty read. Overall, the release focuses on enhancing performance, stability, and compatibility. - [2.0](https://docs.pingcap.com/tidb/stable/release-2.0-ga.md): TiDB 2.0 GA release on April 27, 2018, brings improvements in MySQL compatibility, SQL optimizer, executor, and stability. Key updates include compact data structure for memory usage reduction, Stream Aggregation operator for empty GROUP BY clause, and support for more MySQL syntaxes. TiKV features include `Region Merge`, `Raw DeleteRange` API, and improved read performance using `ReadPool`. TiSpark 1.0 GA provides distributed computing of TiDB data using Apache Spark, with support for gRPC communication framework, calculation pushdown, index related support, cost-based optimization, and multiple Spark interfaces. - [2.0 RC5](https://docs.pingcap.com/tidb/stable/release-2.0-rc.5.md): TiDB 2.0 RC5 was released on April 17, 2018, with improvements in MySQL compatibility, SQL optimization, and stability. Fixes and optimizations were made to TiDB, PD, and TiKV components, including support for Raft Learner, reducing scheduling overhead, and adding new batch operations. The release also addressed issues related to memory usage, error reporting, and configuration adjustments. - [2.0 RC4](https://docs.pingcap.com/tidb/stable/release-2.0-rc.4.md): TiDB 2.0 RC4, released on March 30, 2018, brings improvements in MySQL compatibility, SQL optimization, and stability. Key updates include support for various syntax, bug fixes, and performance optimizations in TiDB, PD, and TiKV. Notable changes include manual Region splitting in PD, memory usage limitation in TiKV, and support for data pattern import. Overall, the release focuses on enhancing functionality and addressing performance issues. - [2.0 RC3](https://docs.pingcap.com/tidb/stable/release-2.0-rc.3.md): TiDB 2.0 RC3, released on March 23, 2018, brings improvements in MySQL compatibility, SQL optimization, and stability. It includes fixes for various issues, optimizations for execution speed, memory control, and DDL job management. PD now supports Region Merge and has optimizations for leader balance and abnormal Regions. TiKV also supports Region Merge, Raft snapshot process, and streaming in Coprocessor, with various improvements in space management and data recovery. - [2.0 RC1](https://docs.pingcap.com/tidb/stable/release-2.0-rc.1.md): TiDB 2.0 RC1, released on March 9, 2018, brings improvements in MySQL compatibility, SQL optimization, and stability. Key updates include memory usage limitation for SQL statements, Stream Aggregate operator support, configuration file validation, and HTTP API for configuration information. TiDB also enhances MySQL syntax compatibility, optimizer, and Boolean field length. PD sees logic and performance optimizations, while TiKV fixes gRPC call and adds gRPC APIs for metrics. Additionally, TiKV checks SSD usage, optimizes read performance, and improves metrics usage. - [1.1 Beta](https://docs.pingcap.com/tidb/stable/release-1.1-beta.md): TiDB 1.1 Beta, released on February 24, 2018, brings significant improvements in MySQL compatibility, SQL optimization, stability, and performance. Key updates include more monitoring metrics, enhanced MySQL syntax compatibility, improved query optimization, and stability fixes. PD introduces new debug interfaces, priority settings, and performance optimizations. TiKV adds support for resolving locks in batches, GC concurrency, and more recovery operations in `tikv-ctl`. Overall, TiDB 1.1 Beta shows great improvement in test results and stability. - [1.1 Alpha](https://docs.pingcap.com/tidb/stable/release-1.1-alpha.md): TiDB 1.1 Alpha, released on January 19, 2018, brings significant improvements in MySQL compatibility, SQL optimization, stability, and performance. Key updates include enhanced SQL parser, query optimizer, and executor, as well as server support for the PROXY protocol. PD now offers more APIs, TLS support, and improved scheduling, while TiKV introduces Raft learner support, TLS, and performance optimizations. Additionally, it enhances data recovery tools and improves flow control mechanisms. - v1.0 - [1.0.8](https://docs.pingcap.com/tidb/stable/release-1.0.8.md): TiDB 1.0.8 is released with updates including fixes for various issues, performance optimizations, and stability improvements. PD and TiKV also have updates related to reducing lock overheat, fixing leader selection issues, and improving starting speed. To upgrade, follow the order of PD -> TiKV -> TiDB. - [1.0.7](https://docs.pingcap.com/tidb/stable/release-1.0.7.md): TiDB 1.0.7 is released with various updates including optimization of commands, fixing data race and resource leak issues, adding session variable for log query control, and improving stability of test results. PD and TiKV also have updates to fix scheduling loss issues, compatibility issues, and add support for table scan and remote mode in tikv-ctl. To upgrade from 1.0.6 to 1.0.7, follow the rolling upgrade order of PD, TiKV, and TiDB. - [1.0.6](https://docs.pingcap.com/tidb/stable/release-1.0.6.md): TiDB 1.0.6 was released on January 08, 2018. Updates include support for Alter Table Auto_Increment syntax, fixing bugs in Cost Based computation and Null Json issue, and support for extension syntax to shard implicit row ID. Other updates include fixing potential DDL issue, considering timezone setting in certain functions, and support for SEPARATOR syntax in GROUP_CONCAT function. PD fixed store selection problem of hot-region scheduler. To upgrade from 1.0.5 to 1.0.6, follow the rolling upgrade order of PD, TiKV, TiDB. - [1.0.5](https://docs.pingcap.com/tidb/stable/release-1.0.5.md): TiDB 1.0.5 was released on December 26, 2017. Updates include adding max value for Auto_Increment ID, fixing goroutine leak, supporting output of slow queries to separate file, loading TimeZone variable from TiKV, and more. PD fixes include balancing leaders and potential panic during bootstrapping. TiKV fixes slow CPU ID retrieval and supports dynamic-level-bytes parameter. Upgrade order is PD -> TiKV -> TiDB. - [1.0.4](https://docs.pingcap.com/tidb/stable/release-1.0.4.md): TiDB 1.0.4 was released on December 11, 2017. Updates include speed improvements, performance enhancements, and fixes for potential issues in TiDB and TiKV. To upgrade from 1.0.3 to 1.0.4, follow the rolling upgrade order of PD, TiKV, and TiDB. - [1.0.3](https://docs.pingcap.com/tidb/stable/release-1.0.3.md): TiDB 1.0.3 was released on November 28, 2017. Updates include performance optimization, new configuration options, and bug fixes. PD now supports adding more schedulers using API, and TiKV has fixed deadlock and leader value issues. To upgrade from 1.0.2 to 1.0.3, follow the rolling upgrade order of PD, TiKV, and TiDB. - [1.0.2](https://docs.pingcap.com/tidb/stable/release-1.0.2.md): TiDB 1.0.2 was released on November 13, 2017. Updates include optimized cost estimation for index point query, support for Alter Table Add Column syntax, and improved query optimization. Placement Driver (PD) scheduling stability was enhanced, and TiKV now supports table splitting and limits key length to 4 KB. Other improvements include more accurate read traffic statistics and bug fixes for LIKE behavior and do_div_mod bug. - [1.0.1](https://docs.pingcap.com/tidb/stable/release-1.0.1.md): TiDB 1.0.1 was released on November 1, 2017. Updates include support for canceling DDL Job, optimizing the `IN` expression, correcting the result type of the `Show` statement, supporting log slow query into a separate log file, and fixing bugs. TiKV now supports flow control with write bytes, reduces Raft allocation, increases coprocessor stack size to 10MB, and removes the useless log from the coprocessor. - [1.0](https://docs.pingcap.com/tidb/stable/release-1.0-ga.md): TiDB 1.0 is released with a focus on MySQL compatibility, SQL optimization, stability, and performance. It includes enhancements to the SQL query optimizer, internal data format optimization, and support for various operators. PD now supports read flow based balancing and setting store weight. TiKV has improved coprocessor support and performance, and added a Debug API. Special thanks to enterprises, open source software, and individual contributors for their support. - [Pre-GA](https://docs.pingcap.com/tidb/stable/release-pre-ga.md): TiDB Pre-GA release on August 30, 2017, focuses on MySQL compatibility, SQL optimization, stability, and performance. TiDB introduces SQL query optimizer enhancements, MySQL compatibility, JSON type support, and memory consumption reduction. Placement Driver (PD) now supports manual leader change, while TiKV uses dedicated Rocksdb for Raft log storage and improves performance. TiDB Connector for Spark Beta Release implements predicates pushdown, aggregation pushdown, and range pruning, capable of running TPC+H queries. - [RC4](https://docs.pingcap.com/tidb/stable/release-rc.4.md): TiDB RC4 is released with a focus on MySQL compatibility, SQL optimization, stability, and performance. Highlights include improved write performance, better query cost estimating, and support for TiSpark to access data in TiKV. Detailed updates include refactoring of the SQL query optimizer, support for JSON type and operations, and optimization of the scheduler in Placement Driver. TiKV now supports RC isolation level, Document Store, and more pushdown functions in Coprocessor. TiSpark beta release includes prediction pushdown, aggregation pushdown, and range pruning, capable of running a full set of TPC-H queries. - [RC3](https://docs.pingcap.com/tidb/stable/release-rc.3.md): TiDB RC3, released on June 16, 2017, focuses on MySQL compatibility, SQL optimization, stability, and performance. Highlights include refined privilege management, accelerated DDL, optimized load balancing, and open-sourced TiDB Ansible for easy cluster management. Detailed updates for TiDB, Placement Driver (PD), and TiKV include improved SQL query optimization, complete privilege management, support for HTTP API, system variables for query concurrency control, and more efficient data balance. PD supports gRPC, disaster recovery toolkit, and hot Region scheduling. TiKV supports gRPC, SST format snapshot, memory leak detection, and improved data importing speed. Overall, the release enhances performance, stability, and management capabilities. - [RC2](https://docs.pingcap.com/tidb/stable/release-rc.2.md): TiDB RC2, released on March 1, 2017, focuses on MySQL compatibility, SQL query optimization, system stability, and performance. It introduces a new permission management mechanism, allowing users to control data access similar to MySQL privilege management. Key improvements include query optimizer enhancements, basic privilege management support, MySQL built-in functions, and performance optimizations. PD now supports location aware replica scheduling and fast scheduling based on region count, while TiKV introduces Async Apply for improved write performance and various optimizations for read and insert performance. Bug fixes and memory leak solutions are also included. - [RC1](https://docs.pingcap.com/tidb/stable/release-rc.1.md): TiDB RC1 was released on December 23, 2016. Updates include improved write speed and reduced disk space usage in TiKV, optimized scheduling strategy framework in PD, and added features in the SQL query optimizer and new tools in TiDB. The release also supports more built-in functions in MySQL and enhances the speed of the `add index` statement.