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v3.0 (stable) dev v2.1
  • Introduction
    • TiDB Introduction
    • Benchmarks
      • How to Test TiDB Using Sysbench
      • How to Run TPC-C Test on TiDB
      • Sysbench Performance Test - v3.0 vs. v2.1
      • TPC-C Performance Test - v3.0 vs. v2.1
      • Interaction Test on Online Workloads and `ADD INDEX` Operations
      • TiDB in Kubernetes Sysbench Test
      • DM 1.0-alpha Benchmark Report
      • DM 1.0-GA Benchmark Report
  • Concepts
    • Architecture
    • Key Features
      • Horizontal Scalability
      • MySQL Compatible Syntax
      • Replicate from and to MySQL
      • Distributed Transactions with Strong Consistency
      • Cloud Native Architecture
      • Minimize ETL with HTAP
      • Fault Tolerance & Recovery with Raft
      • Automatic Rebalancing
      • Deployment and Orchestration with Ansible, Kubernetes, Docker
      • JSON Support
      • Spark Integration
      • Read Historical Data Without Restoring from Backup
      • Fast Import and Restore of Data
      • Hybrid of Column and Row Storage
      • SQL Plan Management
      • Open Source
      • Online Schema Changes
  • How-to
    • Get Started
      • Start a Cluster
        • From Binary
        • From Homebrew
        • From DBdeployer
      • Explore SQL with TiDB
      • Import Example Database
      • Read Historical Data
      • TiDB Binlog Tutorial
      • TiDB Data Migration Tutorial
      • TiSpark Quick Start Guide
    • Deploy
      • Hardware Recommendations
      • From Binary Tarball
        • For Testing Environments
        • For Production Environments
      • Orchestrated Deployment
        • Ansible Deployment (Recommended)
        • Ansible Offline Deployment
        • Docker Deployment
      • Geographic Redundancy
        • Overview
        • Configure Location Awareness
      • Data Migration with Ansible
    • Configure
      • Time Zone
      • Memory Control
    • Secure
      • Transport Layer Security (TLS)
        • Enable TLS For MySQL Clients
        • Enable TLS Between TiDB Components
      • Generate Self-signed Certificates
    • Monitor
      • Overview
      • Monitor a TiDB Cluster
    • Migrate
      • Overview
      • Migrate from MySQL
        • Migrate the Full Data
        • Migrate the Incremental Data
      • Migrate from Aurora
      • Migrate from CSV
    • Maintain
      • Common Ansible Operations
      • Backup and Restore
      • Identify Slow Queries
    • Scale
      • Scale using Ansible
      • Scale a TiDB Cluster
    • Upgrade
      • Upgrade to TiDB 3.0
      • Rolling updates with Ansible
    • Troubleshoot
      • Troubleshoot Cluster Setup
      • Troubleshoot TiDB Lightning
  • Reference
    • SQL
      • MySQL Compatibility
      • SQL Language Structure
        • Literal Values
        • Schema Object Names
        • Keywords and Reserved Words
        • User-Defined Variables
        • Expression Syntax
        • Comment Syntax
      • Data Types
        • Overview
        • Default Values
        • Numeric Types
          • `BIT`
          • `BOOL|BOOLEAN`
          • `TINYINT`
          • `SMALLINT`
          • `MEDIUMINT`
          • `INT|INTEGER`
          • `BIGINT`
          • `DECIMAL`
          • `FLOAT`
          • `DOUBLE`
        • Date and Time Types
          • `DATE`
          • `DATETIME`
          • `TIMESTAMP`
          • `TIME`
          • `YEAR`
        • String Types
          • `CHAR`
          • `VARCHAR`
          • `TEXT`
          • `LONGTEXT`
          • `BINARY`
          • `VARBINARY`
          • `TINYBLOB`
          • `BLOB`
          • `MEDIUMBLOB`
          • `LONGBLOB`
          • `ENUM`
          • `SET`
        • JSON Type
      • Functions and Operators
        • Function and Operator Reference
        • 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
      • SQL Statements
        • `ADD COLUMN`
        • `ADD INDEX`
        • `ADMIN`
        • `ALTER DATABASE`
        • `ALTER TABLE`
        • `ALTER USER`
        • `ANALYZE TABLE`
        • `BEGIN`
        • `COMMIT`
        • `CREATE DATABASE`
        • `CREATE INDEX`
        • `CREATE TABLE LIKE`
        • `CREATE TABLE`
        • `CREATE USER`
        • `CREATE VIEW`
        • `DEALLOCATE`
        • `DELETE`
        • `DESC`
        • `DESCRIBE`
        • `DO`
        • `DROP COLUMN`
        • `DROP DATABASE`
        • `DROP INDEX`
        • `DROP TABLE`
        • `DROP USER`
        • `DROP VIEW`
        • `EXECUTE`
        • `EXPLAIN ANALYZE`
        • `EXPLAIN`
        • `FLUSH PRIVILEGES`
        • `FLUSH STATUS`
        • `FLUSH TABLES`
        • `GRANT <privileges>`
        • `INSERT`
        • `KILL [TIDB]`
        • `LOAD DATA`
        • `MODIFY COLUMN`
        • `PREPARE`
        • `RECOVER TABLE`
        • `RENAME INDEX`
        • `RENAME TABLE`
        • `REPLACE`
        • `REVOKE <privileges>`
        • `ROLLBACK`
        • `SELECT`
        • `SET [NAMES|CHARACTER SET]`
        • `SET PASSWORD`
        • `SET TRANSACTION`
        • `SET [GLOBAL|SESSION] <variable>`
        • `SHOW CHARACTER SET`
        • `SHOW COLLATION`
        • `SHOW [FULL] COLUMNS FROM`
        • `SHOW CREATE TABLE`
        • `SHOW CREATE USER`
        • `SHOW DATABASES`
        • `SHOW ENGINES`
        • `SHOW ERRORS`
        • `SHOW [FULL] FIELDS FROM`
        • `SHOW GRANTS`
        • `SHOW INDEXES [FROM|IN]`
        • `SHOW INDEX [FROM|IN]`
        • `SHOW KEYS [FROM|IN]`
        • `SHOW PRIVILEGES`
        • `SHOW [FULL] PROCESSSLIST`
        • `SHOW SCHEMAS`
        • `SHOW [FULL] TABLES`
        • `SHOW TABLE REGIONS`
        • `SHOW TABLE STATUS`
        • `SHOW [GLOBAL|SESSION] VARIABLES`
        • `SHOW WARNINGS`
        • `SPLIT REGION`
        • `START TRANSACTION`
        • `TRACE`
        • `TRUNCATE`
        • `UPDATE`
        • `USE`
      • Constraints
      • Generated Columns
      • Partitioning
      • Character Set
      • SQL Mode
      • Views
    • Configuration
      • tidb-server
        • MySQL System Variables
        • TiDB Specific System Variables
        • Configuration Flags
        • Configuration File
      • pd-server
        • Configuration Flags
        • Configuration File
      • tikv-server
        • Configuration Flags
        • Configuration File
    • Security
      • Security Compatibility with MySQL
      • The TiDB Access Privilege System
      • TiDB User Account Management
      • Role-Based Access Control
    • Transactions
      • Overview
      • Transaction Model
      • Isolation Levels
      • Pessimistic Transactions
    • System Databases
      • `mysql`
      • `information_schema`
    • Errors Codes
    • Supported Client Drivers
    • Garbage Collection (GC)
      • GC Overview
      • GC Configuration
    • Performance
      • Overview
      • Understanding the Query Execution Plan
      • Introduction to Statistics
      • Optimizer Hints
      • Check the TiDB Cluster Status Using SQL Statements
      • Execution Plan Binding
      • Statement Summary Table
      • Tune TiKV
    • Key Monitoring Metrics
      • Overview
      • TiDB
      • PD
      • TiKV
    • Alert Rules
    • Best Practices
    • TiSpark
    • TiDB Binlog
      • Overview
      • Deploy
      • Maintain
      • Monitor
      • Upgrade
      • Reparo
      • Binlog Slave Client
      • FAQ
    • Tools
      • Mydumper
      • Syncer
      • Loader
      • TiDB Data Migration
        • Overview
          • DM Overview
          • Restrictions
          • DM-worker
          • DM Relay Log
        • Features
          • Table Routing
          • Black and White Lists
          • Binlog Event Filter
          • Column Mapping
          • Replication Delay Monitoring
          • Sharding Support
            • Introduction
            • Restrictions
            • Handle Sharding DDL Locks Manually
        • Usage Scenarios
          • Simple Scenario
          • Shard Merge Scenario
        • Deploy
        • Configure
          • Overview
          • Task Configuration
        • Manage the DM Cluster
          • Cluster Operations
          • Cluster Upgrade
        • Manage Replication Tasks
          • Manage Tasks
          • Precheck Tasks
          • Query Task Status
        • Monitor
        • Migrate from MySQL compatible database
          • Migrate from Aurora
        • Troubleshoot
          • DM Troubleshooting
          • Error Description
          • Error Handling
        • FAQ
      • TiDB Lightning
        • Overview
        • Deployment
        • Checkpoints
        • Table Filter
        • CSV Support
        • Monitor
        • Troubleshoot
        • FAQ
      • sync-diff-inspector
      • PD Control
      • PD Recover
      • TiKV Control
      • TiDB Control
      • Download
  • TiDB in Kubernetes
    • About TiDB Operator
    • Get Started
      • kind
      • GKE
      • Minikube
    • Deploy
      • Prerequisites
      • TiDB Operator
      • TiDB in General Kubernetes
      • TiDB in AWS EKS
      • TiDB in GCP GKE
      • TiDB in Alibaba Cloud ACK
      • Access TiDB in Kubernetes
    • Configure
      • Cluster Initialization
    • Monitor
    • Maintain
      • Destroy a TiDB cluster
      • Maintain a Hosting Kubernetes Node
      • Backup and Restore
      • Restore Data with TiDB Lightning
      • Collect Logs
      • Automatic Failover
      • TiDB Binlog
    • Scale
    • Upgrade
      • TiDB Cluster
      • TiDB Operator
    • Reference
      • Configuration
        • TiDB Cluster
        • Backup
        • PV
        • TiDB Drainer
      • Tools
        • tkctl
        • Tools in Kubernetes
    • Troubleshoot
    • FAQs
  • FAQs
    • TiDB FAQs
    • TiDB Lightning FAQs
    • Upgrade FAQs
  • Support
    • Support Resources
    • Report an Issue
  • Contribute
    • Contribute to TiDB
    • Improve the Docs
  • Adopters
  • Roadmap
  • Releases
    • v3.0
      • 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
      • 2.1.18
      • 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

DESC

This statement is an alias to EXPLAIN. It is included for compatibility with MySQL.

"DESC | TiDB SQL Statement Reference" was last updated Sep 4 2019: dev, v3.0, v2.1: update links according to the new link format (#1501) (e8f970f)
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