TOC.md

• About TiDB
  • TiDB Introduction
  • TiDB 5.3 Release Notes
  • Basic Features
  • Experimental Features
  • Benchmarks
    • v5.3 Sysbench Performance Test Report
    • v5.3 TPC-C Performance Test Report
    • v5.4 MPP mode TPC-H 100GB Performance Test
  • MySQL Compatibility
  • TiDB Limitations
  • TiDB Adopters
  • Credits
• Quick Start
  • Try Out TiDB
  • Try Out HTAP
  • Learn TiDB SQL
  • Learn HTAP
  • Import Example Database
• Deploy
  • Software and Hardware Requirements
  • Environment Configuration Checklist
  • Plan Cluster Topology
    • Minimal Topology
    • TiFlash Topology
    • TiCDC Topology
    • TiDB Binlog Topology
    • TiSpark Topology
    • Cross-DC Topology
    • Hybrid Topology
  • Install and Start
    • Use TiUP (Recommended)
    • Deploy in Kubernetes
  • Verify Cluster Status
  • Test Cluster Performance
    • Test TiDB Using Sysbench
    • Test TiDB Using TPC-C
• Migrate
  • Overview
  • Migration Tools
  • Migration Scenarios
    • Migrate from Aurora
    • Migrate MySQL of Small Datasets
    • Migrate MySQL of Large Datasets
    • Migrate and Merge MySQL Shards of Small Datasets
    • Migrate and Merge MySQL Shards of Large Datasets
    • Migrate from CSV Files
    • Migrate from SQL Files
    • Replicate Incremental Data between TiDB Clusters
  • Advanced Migration
    • Continuous Replication with gh-ost or pt-osc
    • Filter Binlog Events
    • Filter DML Events Using SQL Expressions
    • Migrate to a Downstream Table with More Columns
• Maintain
  • Upgrade
    • Use TiUP (Recommended)
    • Use TiDB Operator
  • Scale
    • Use TiUP (Recommended)
    • Use TiDB Operator
  • Backup and Restore
    • Use BR Tool (Recommended)
      • BR Tool Overview
      • Use BR Command-line for Backup and Restoration
      • BR Use Cases
      • External Storages
      • BR Features
        • Auto Tune
      • BR FAQ
  • Configure Time Zone
  • Daily Checklist
  • Maintain TiFlash
  • Maintain TiDB Using TiUP
  • Modify Configuration Online
  • Online Unsafe Recovery
• Monitor and Alert
  • Monitoring Framework Overview
  • Monitoring API
  • Deploy Monitoring Services
  • Export Grafana Snapshots
  • TiDB Cluster Alert Rules
  • TiFlash Alert Rules
• Troubleshoot
  • TiDB Troubleshooting Map
  • Identify Slow Queries
  • Analyze Slow Queries
  • SQL Diagnostics
  • Identify Expensive Queries
  • Statement Summary Tables
  • Troubleshoot Hotspot Issues
  • Troubleshoot Increased Read and Write Latency
  • Save and Restore the On-Site Information of a Cluster
  • Troubleshoot Cluster Setup
  • Troubleshoot High Disk I/O Usage
  • Troubleshoot Lock Conflicts
  • Troubleshoot TiFlash
  • Troubleshoot Write Conflicts in Optimistic Transactions
• Performance Tuning
  • System Tuning
    • Operating System Tuning
  • Software Tuning
    • Configuration
      • Tune TiDB Memory
      • Tune TiKV Threads
      • Tune TiKV Memory
      • TiKV Follower Read
      • TiFlash Tuning
    • Coprocessor Cache
  • SQL Tuning
    • Overview
    • Understanding the Query Execution Plan
      • Overview
      • EXPLAIN Walkthrough
      • Indexes
      • Joins
      • MPP Queries
      • Subqueries
      • Aggregation
      • Views
      • Partitions
    • SQL Optimization Process
      • Overview
      • Logic Optimization
        • Overview
        • Subquery Related Optimizations
        • Column Pruning
        • Decorrelation of Correlated Subquery
        • Eliminate Max/Min
        • Predicates Push Down
        • Partition Pruning
        • TopN and Limit Push Down
        • Join Reorder
      • Physical Optimization
        • Overview
        • Index Selection
        • Statistics
        • Wrong Index Solution
        • Distinct Optimization
      • Prepare Execution Plan Cache
    • Control Execution Plans
      • Overview
      • Optimizer Hints
      • SQL Plan Management
      • The Blocklist of Optimization Rules and Expression Pushdown
• Tutorials
  • Multiple Data Centers in One City Deployment
  • Three Data Centers in Two Cities Deployment
  • Two Data Centers in One City Deployment
  • Read Historical Data
    • Use Stale Read (Recommended)
      • Usage Scenarios of Stale Read
      • Perform Stale Read Using As OF TIMESTAMP
    • Use the tidb_snapshot System Variable
  • Best Practices
    • Use TiDB
    • Java Application Development
    • Use HAProxy
    • Highly Concurrent Write
    • Grafana Monitoring
    • PD Scheduling
    • TiKV Performance Tuning with Massive Regions
    • Three-node Hybrid Deployment
    • Local Read Under Three Data Centers Deployment
  • Use Placement Rules
  • Use Load Base Split
  • Use Store Limit
• TiDB Tools
  • Overview
  • Use Cases
  • Download
  • TiUP
    • Documentation Map
    • Overview
    • Terminology and Concepts
    • Manage TiUP Components
    • FAQ
    • Troubleshooting Guide
    • Reference Guide
    • Cluster Topology Reference
    • Mirror Reference Guide
    • TiUP Components
      • tiup-playground
      • tiup-cluster
      • tiup-mirror
      • tiup-bench
  • TiDB Operator
  • Backup & Restore (BR)
    • BR Tool Overview
    • Use BR Command-line for Backup and Restoration
    • BR Use Cases
    • External Storages
    • BR Features
      • Auto Tune
    • BR FAQ
  • TiDB Binlog
    • Overview
    • Quick Start
    • Deploy
    • Maintain
    • Configure
      • Pump
      • Drainer
    • Upgrade
    • Monitor
    • Reparo
    • binlogctl
    • Binlog Consumer Client
    • TiDB Binlog Relay Log
    • Bidirectional Replication Between TiDB Clusters
    • Glossary
    • Troubleshoot
      • Troubleshoot
      • Handle Errors
    • FAQ
  • TiDB Lightning
    • Overview
    • Tutorial
    • Deploy
    • Precheck
    • Configure
    • Key Features
      • Checkpoints
      • Table Filter
      • CSV Support
      • Backends
      • Import Data in Parallel
      • Error Resolution
      • Web Interface
    • Monitor
    • FAQ
    • Glossary
  • TiDB Data Migration
    • About TiDB Data Migration
      • DM Overview
      • Basic Features
        • Table Routing
        • Block and Allow Lists
        • Binlog Event Filter
      • Advanced Features
        • Merge and Migrate Data from Sharded Tables
          • Overview
          • Pessimistic Mode
          • Optimistic Mode
        • Migrate from MySQL Databases that Use GH-ost/PT-osc
        • Filter Certain Row Changes Using SQL Expressions
      • DM Architecture
      • Benchmarks
    • Quick Start
      • Quick Start
      • Deploy a DM cluster Using TiUP
      • Create a Data Source
      • Data Migration Scenarios
        • Data Migration Scenario Overview
        • Migrate Data from Multiple Data Sources to TiDB
        • Migrate Sharded Schemas and Tables to TiDB
        • Migrate Incremental Data to TiDB
        • Migrate Tables when There Are More Columns Downstream
    • Deploy
      • Software and Hardware Requirements
      • Deploy a DM Cluster
        • Use TiUP (Recommended)
        • Use TiUP Offline
        • Use Binary
        • Use Kubernetes
      • Migrate Data Using DM
      • Test DM Performance
    • Maintain
      • Tools
        • Maintain DM Clusters Using TiUP (Recommended)
        • Maintain DM Clusters Using dmctl
        • Maintain DM Clusters Using OpenAPI
      • Cluster Upgrade
        • Manually Upgrade from v1.0.x to v2.0+
      • Manage Data Source
      • Manage a Data Migration Task
        • Task Configuration Guide
        • Precheck a Task
        • Create a Task
        • Query Status
        • Pause a Task
        • Resume a Task
        • Stop a Task
        • Export and Import Data Sources and Task Configuration of Clusters
        • Handle Failed DDL Statements
      • Manually Handle Sharding DDL Lock
      • Manage Schemas of Tables to be Migrated
      • Handle Alerts
      • Daily Check
    • Usage Scenarios
      • Migrate from Aurora to TiDB
      • Migrate when TiDB Tables Have More Columns
      • Switch the MySQL Instance to Be Migrated
    • Troubleshoot
      • Handle Errors
      • Handle Performance Issues
    • Performance Tuning
      • Optimize Configuration
    • Reference
      • Architecture
        • DM Architecture Overview
        • DM-worker
      • Command-line Flags
      • Configuration
        • Overview
        • DM-master Configuration
        • DM-worker Configuration
        • Upstream Database Configuration
        • Data Migration Task Configuration
    • Secure
      • Enable TLS for DM Connections
      • Generate Self-signed Certificates
      • Monitoring Metrics
      • Alert Rules
      • Error Codes
    • FAQ
    • Glossary
    • Release Notes
  • TiCDC
    • Overview
    • Deploy
    • Maintain
    • Troubleshoot
    • Monitor
    • Alert Rules
    • TiCDC OpenAPI
    • TiCDC Open Protocol
    • TiCDC Canal-JSON Protocol
    • Integrate TiDB with Confluent Platform
    • Glossary
  • Dumpling
  • sync-diff-inspector
    • Overview
    • Data Check for Tables with Different Schema/Table Names
    • Data Check in the Sharding Scenario
    • Data Check for TiDB Upstream/Downstream Clusters
    • Data Check in the DM Replication Scenario
  • TiSpark
    • User Guide
• Reference
  • Cluster Architecture
    • Overview
    • Storage
    • Computing
    • Scheduling
  • Key Monitoring Metrics
    • Overview
    • TiDB
    • PD
    • TiKV
    • TiFlash
    • TiCDC
  • Secure
    • Enable TLS Between TiDB Clients and Servers
    • Enable TLS Between TiDB Components
    • Generate Self-signed Certificates
    • Encryption at Rest
    • Enable Encryption for Disk Spill
    • Log Redaction
  • Privileges
    • Security Compatibility with MySQL
    • Privilege Management
    • User Account Management
    • Role-Based Access Control
    • Certificate-Based Authentication
  • SQL
    • SQL Language Structure and Syntax
      • Attributes
        • AUTO_INCREMENT
        • AUTO_RANDOM
        • SHARD_ROW_ID_BITS
      • Literal Values
      • Schema Object Names
      • Keywords and Reserved Words
      • User-Defined Variables
      • Expression Syntax
      • Comment Syntax
    • SQL Statements
      • ADD COLUMN
      • ADD INDEX
      • ADMIN
      • ADMIN CANCEL DDL
      • ADMIN CHECKSUM TABLE
      • ADMIN CHECK [TABLE|INDEX]
      • ADMIN SHOW DDL [JOBS|QUERIES]
      • ADMIN SHOW TELEMETRY
      • ALTER DATABASE
      • ALTER INDEX
      • ALTER INSTANCE
      • ALTER PLACEMENT POLICY
      • ALTER TABLE
      • ALTER USER
      • ANALYZE TABLE
      • BACKUP
      • BEGIN
      • CHANGE COLUMN
      • COMMIT
      • CHANGE DRAINER
      • CHANGE PUMP
      • CREATE [GLOBAL|SESSION] BINDING
      • CREATE DATABASE
      • CREATE INDEX
      • CREATE PLACEMENT POLICY
      • CREATE ROLE
      • CREATE SEQUENCE
      • CREATE TABLE LIKE
      • CREATE TABLE
      • CREATE USER
      • CREATE VIEW
      • DEALLOCATE
      • DELETE
      • DESC
      • DESCRIBE
      • DO
      • DROP [GLOBAL|SESSION] BINDING
      • DROP COLUMN
      • DROP DATABASE
      • DROP INDEX
      • DROP PLACEMENT POLICY
      • DROP ROLE
      • DROP SEQUENCE
      • DROP STATS
      • DROP TABLE
      • DROP USER
      • DROP VIEW
      • EXECUTE
      • EXPLAIN ANALYZE
      • EXPLAIN
      • FLASHBACK TABLE
      • FLUSH PRIVILEGES
      • FLUSH STATUS
      • FLUSH TABLES
      • GRANT <privileges>
      • GRANT <role>
      • INSERT
      • KILL [TIDB]
      • LOAD DATA
      • LOAD STATS
      • MODIFY COLUMN
      • PREPARE
      • RECOVER TABLE
      • RENAME INDEX
      • RENAME TABLE
      • REPLACE
      • RESTORE
      • REVOKE <privileges>
      • REVOKE <role>
      • ROLLBACK
      • SELECT
      • SET DEFAULT ROLE
      • SET [NAMES|CHARACTER SET]
      • SET PASSWORD
      • SET ROLE
      • SET TRANSACTION
      • SET [GLOBAL|SESSION] <variable>
      • SHOW ANALYZE STATUS
      • SHOW [BACKUPS|RESTORES]
      • SHOW [GLOBAL|SESSION] BINDINGS
      • SHOW BUILTINS
      • SHOW CHARACTER SET
      • SHOW COLLATION
      • SHOW [FULL] COLUMNS FROM
      • SHOW CONFIG
      • SHOW CREATE PLACEMENT POLICY
      • SHOW CREATE SEQUENCE
      • SHOW CREATE TABLE
      • SHOW CREATE USER
      • SHOW DATABASES
      • SHOW DRAINER STATUS
      • SHOW ENGINES
      • SHOW ERRORS
      • SHOW [FULL] FIELDS FROM
      • SHOW GRANTS
      • SHOW INDEX [FROM|IN]
      • SHOW INDEXES [FROM|IN]
      • SHOW KEYS [FROM|IN]
      • SHOW MASTER STATUS
      • SHOW PLACEMENT
      • SHOW PLACEMENT FOR
      • SHOW PLACEMENT LABELS
      • SHOW PLUGINS
      • SHOW PRIVILEGES
      • SHOW [FULL] PROCESSSLIST
      • SHOW PROFILES
      • SHOW PUMP STATUS
      • SHOW SCHEMAS
      • SHOW STATS_HEALTHY
      • SHOW STATS_HISTOGRAMS
      • SHOW STATS_META
      • SHOW STATUS
      • SHOW TABLE NEXT_ROW_ID
      • SHOW TABLE REGIONS
      • SHOW TABLE STATUS
      • SHOW [FULL] TABLES
      • SHOW [GLOBAL|SESSION] VARIABLES
      • SHOW WARNINGS
      • SHUTDOWN
      • SPLIT REGION
      • START TRANSACTION
      • TABLE
      • TRACE
      • TRUNCATE
      • UPDATE
      • USE
      • WITH
    • Data Types
      • Overview
      • Default Values
      • Numeric Types
      • Date and Time Types
      • String Types
      • JSON Type
    • Functions and Operators
      • Overview
      • Type Conversion in Expression Evaluation
      • Operators
      • Control Flow Functions
      • String Functions
      • Numeric Functions and Operators
      • Date and Time Functions
      • Bit Functions and Operators
      • Cast Functions and Operators
      • Encryption and Compression Functions
      • Information Functions
      • JSON Functions
      • Aggregate (GROUP BY) Functions
      • Window Functions
      • Miscellaneous Functions
      • Precision Math
      • Set Operations
      • List of Expressions for Pushdown
      • TiDB Specific Functions
    • Clustered Indexes
    • Constraints
    • Generated Columns
    • SQL Mode
    • Table Attributes
    • Transactions
      • Overview
      • Isolation Levels
      • Optimistic Transactions
      • Pessimistic Transactions
    • Garbage Collection (GC)
      • Overview
      • Configuration
    • Views
    • Partitioning
    • Temporary Tables
    • [Character Set and Collation]
      • Overview
      • GBK
    • Placement Rules in SQL
    • System Tables
      • mysql
      • INFORMATION_SCHEMA
        • Overview
        • ANALYZE_STATUS
        • CLIENT_ERRORS_SUMMARY_BY_HOST
        • CLIENT_ERRORS_SUMMARY_BY_USER
        • CLIENT_ERRORS_SUMMARY_GLOBAL
        • CHARACTER_SETS
        • CLUSTER_CONFIG
        • CLUSTER_HARDWARE
        • CLUSTER_INFO
        • CLUSTER_LOAD
        • CLUSTER_LOG
        • CLUSTER_SYSTEMINFO
        • COLLATIONS
        • COLLATION_CHARACTER_SET_APPLICABILITY
        • COLUMNS
        • DATA_LOCK_WAITS
        • DDL_JOBS
        • DEADLOCKS
        • ENGINES
        • INSPECTION_RESULT
        • INSPECTION_RULES
        • INSPECTION_SUMMARY
        • KEY_COLUMN_USAGE
        • METRICS_SUMMARY
        • METRICS_TABLES
        • PARTITIONS
        • PLACEMENT_RULES
        • PROCESSLIST
        • REFERENTIAL_CONSTRAINTS
        • SCHEMATA
        • SEQUENCES
        • SESSION_VARIABLES
        • SLOW_QUERY
        • STATISTICS
        • TABLES
        • TABLE_CONSTRAINTS
        • TABLE_STORAGE_STATS
        • TIDB_HOT_REGIONS
        • TIDB_HOT_REGIONS_HISTORY
        • TIDB_INDEXES
        • TIDB_SERVERS_INFO
        • TIDB_TRX
        • TIFLASH_REPLICA
        • TIKV_REGION_PEERS
        • TIKV_REGION_STATUS
        • TIKV_STORE_STATUS
        • USER_PRIVILEGES
        • VIEWS
      • METRICS_SCHEMA
  • UI
    • TiDB Dashboard
      • Overview
      • Maintain
        • Deploy
        • Reverse Proxy
        • User Management
        • Secure
      • Access
      • Overview Page
      • Cluster Info Page
      • Key Visualizer Page
      • Metrics Relation Graph
      • SQL Statements Analysis
        • SQL Statements Page
        • SQL Details Page
      • Slow Queries Page
      • Cluster Diagnostics
        • Access Cluster Diagnostics Page
        • View Diagnostics Report
        • Use Diagnostics
      • Search Logs Page
      • [Instance Profiling]
        • Manual Profiling
        • Continuous Profiling
      • Session Management and Configuration
        • Share Session
        • Configure SSO
      • FAQ
  • CLI
    • tikv-ctl
    • pd-ctl
    • tidb-ctl
    • pd-recover
  • Command Line Flags
    • tidb-server
    • tikv-server
    • tiflash-server
    • pd-server
  • Configuration File Parameters
    • tidb-server
    • tikv-server
    • tiflash-server
    • pd-server
  • System Variables
  • Storage Engines
    • TiKV
      • TiKV Overview
      • RocksDB Overview
      • Titan Overview
      • Titan Configuration
    • TiFlash
      • Overview
      • Use TiFlash
  • Telemetry
  • Errors Codes
  • Table Filter
  • Schedule Replicas by Topology Labels
• FAQs
  • TiDB FAQs
  • SQL FAQs
  • Deploy and Maintain FAQs
  • Upgrade FAQs
  • High Availability FAQs
  • High Reliability FAQs
  • Migration FAQs
• Glossary
• Release Notes
  • All Releases
  • Release Timeline
  • v5.3
    • 5.3.0
  • v5.2
    • 5.2.3
    • 5.2.2
    • 5.2.1
    • 5.2.0
  • v5.1
    • 5.1.3
    • 5.1.2
    • 5.1.1
    • 5.1.0
  • v5.0
    • 5.0.6
    • 5.0.5
    • 5.0.4
    • 5.0.3
    • 5.0.2
    • 5.0.1
    • 5.0 GA
    • 5.0.0-rc
  • v4.0
    • 4.0.16
    • 4.0.15
    • 4.0.14
    • 4.0.13
    • 4.0.12
    • 4.0.11
    • 4.0.10
    • 4.0.9
    • 4.0.8
    • 4.0.7
    • 4.0.6
    • 4.0.5
    • 4.0.4
    • 4.0.3
    • 4.0.2
    • 4.0.1
    • 4.0 GA
    • 4.0.0-rc.2
    • 4.0.0-rc.1
    • 4.0.0-rc
    • 4.0.0-beta.2
    • 4.0.0-beta.1
    • 4.0.0-beta
  • v3.1
    • 3.1.2
    • 3.1.1
    • 3.1.0 GA
    • 3.1.0-rc
    • 3.1.0-beta.2
    • 3.1.0-beta.1
    • 3.1.0-beta
  • v3.0
    • 3.0.20
    • 3.0.19
    • 3.0.18
    • 3.0.17
    • 3.0.16
    • 3.0.15
    • 3.0.14
    • 3.0.13
    • 3.0.12
    • 3.0.11
    • 3.0.10
    • 3.0.9
    • 3.0.8
    • 3.0.7
    • 3.0.6
    • 3.0.5
    • 3.0.4
    • 3.0.3
    • 3.0.2
    • 3.0.1
    • 3.0 GA
    • 3.0.0-rc.3
    • 3.0.0-rc.2
    • 3.0.0-rc.1
    • 3.0.0-beta.1
    • 3.0.0-beta
  • v2.1
    • 2.1.19
    • 2.1.18
    • 2.1.17
    • 2.1.16
    • 2.1.15
    • 2.1.14
    • 2.1.13
    • 2.1.12
    • 2.1.11
    • 2.1.10
    • 2.1.9
    • 2.1.8
    • 2.1.7
    • 2.1.6
    • 2.1.5
    • 2.1.4
    • 2.1.3
    • 2.1.2
    • 2.1.1
    • 2.1 GA
    • 2.1 RC5
    • 2.1 RC4
    • 2.1 RC3
    • 2.1 RC2
    • 2.1 RC1
    • 2.1 Beta
  • v2.0
    • 2.0.11
    • 2.0.10
    • 2.0.9
    • 2.0.8
    • 2.0.7
    • 2.0.6
    • 2.0.5
    • 2.0.4
    • 2.0.3
    • 2.0.2
    • 2.0.1
    • 2.0
    • 2.0 RC5
    • 2.0 RC4
    • 2.0 RC3
    • 2.0 RC1
    • 1.1 Beta
    • 1.1 Alpha
  • v1.0
    • 1.0.8
    • 1.0.7
    • 1.0.6
    • 1.0.5
    • 1.0.4
    • 1.0.3
    • 1.0.2
    • 1.0.1
    • 1.0
    • Pre-GA
    • RC4
    • RC3
    • RC2
    • RC1