- 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
- Key Features
- Get Started
- From Binary Tarball
- Orchestrated Deployment
- Geographic Redundancy
- SQL Language Structure
- Data Types
- Numeric Types
- Date and Time Types
- String Types
- Functions and Operators
- Function and Operator Reference
- Type Conversion in Expression Evaluation
- 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
- List of Expressions for Pushdown
- SQL Statements
ADMIN CANCEL DDL
ADMIN CHECKSUM TABLE
ADMIN CHECK [TABLE|INDEX]
ADMIN SHOW DDL [JOBS|QUERIES]
CREATE TABLE LIKE
SET DEFAULT ROLE
SET [NAMES|CHARACTER SET]
SET [GLOBAL|SESSION] <variable>
SHOW ANALYZE STATUS
SHOW CHARACTER SET
SHOW [FULL] COLUMNS FROM
SHOW CREATE TABLE
SHOW CREATE USER
SHOW [FULL] FIELDS FROM
SHOW INDEXES [FROM|IN]
SHOW INDEX [FROM|IN]
SHOW KEYS [FROM|IN]
SHOW [FULL] PROCESSSLIST
SHOW [FULL] TABLES
SHOW TABLE REGIONS
SHOW TABLE STATUS
SHOW [GLOBAL|SESSION] VARIABLES
- System Databases
- Garbage Collection (GC)
- Understanding the Query Execution Plan
- The Blocklist of Optimization Rules and Expression Pushdown
- Introduction to Statistics
- TopN and Limit Push Down
- Optimizer Hints
- Check the TiDB Cluster Status Using SQL Statements
- Execution Plan Binding
- Statement Summary Table
- Tune TiKV
- Operating System Tuning
- Column Pruning
- Key Monitoring Metrics
- Best Practices
- TiDB Binlog
- Binlog Consumer Client
- TiDB Binlog Relay Log
- Bidirectional Replication Between TiDB Clusters
- TiDB Lightning
- All Releases
This statement is a TiDB extension syntax, used to view the status of TiDB and check the data of tables in TiDB.
To view the currently running DDL jobs, use
ADMIN SHOW DDL:
ADMIN SHOW DDL;
To view all the results in the current DDL job queue (including tasks that are running and waiting to be run) and the last ten results in the completed DDL job queue, use
ADMIN SHOW DDL JOBS:
ADMIN SHOW DDL JOBS;
To view the original SQL statements of the DDL job corresponding to
ADMIN SHOW DDL JOB QUERIES:
ADMIN SHOW DDL JOB QUERIES job_id [, job_id] ...;
You can only searches the running DDL job corresponding to
job_id and the last ten results in the DDL history job queue.
To cancel the currently running DDL jobs and return whether the corresponding jobs are successfully cancelled, use
ADMIN CANCEL DDL JOBS:
ADMIN CANCEL DDL JOBS job_id [, job_id] ...;
If the operation fails to cancel the jobs, specific reasons are displayed.
- Only this operation can cancel DDL jobs. All other operations and environment changes (such as machine restart and cluster restart) cannot cancel these jobs.
- This operation can cancel multiple DDL jobs at the same time. You can get the ID of DDL jobs using the
ADMIN SHOW DDL JOBSstatement.
- If the jobs you want to cancel are finished, the cancellation operation fails.
To check the consistency of all the data and corresponding indexes in the
tbl_name table, use
ADMIN CHECK TABLE：
ADMIN CHECK TABLE tbl_name [, tbl_name] ...;
If the consistency check is passed, an empty result is returned. Otherwise, an error message is returned indicating that the data is inconsistent.
AdminStmt ::= 'ADMIN' ( 'SHOW' ( 'DDL' ( 'JOBS' Int64Num? WhereClauseOptional | 'JOB' 'QUERIES' NumList )? | TableName 'NEXT_ROW_ID' | 'SLOW' AdminShowSlow ) | 'CHECK' ( 'TABLE' TableNameList | 'INDEX' TableName Identifier ( HandleRange ( ',' HandleRange )* )? ) | 'RECOVER' 'INDEX' TableName Identifier | 'CLEANUP' ( 'INDEX' TableName Identifier | 'TABLE' 'LOCK' TableNameList ) | 'CHECKSUM' 'TABLE' TableNameList | 'CANCEL' 'DDL' 'JOBS' NumList | 'RELOAD' ( 'EXPR_PUSHDOWN_BLACKLIST' | 'OPT_RULE_BLACKLIST' | 'BINDINGS' ) | 'PLUGINS' ( 'ENABLE' | 'DISABLE' ) PluginNameList | 'REPAIR' 'TABLE' TableName CreateTableStmt | ( 'FLUSH' | 'CAPTURE' | 'EVOLVE' ) 'BINDINGS' )
mysql> admin show ddl jobs; +--------+---------+------------+---------------+----------------------+-----------+----------+-----------+-----------------------------------+---------------+ | JOB_ID | DB_NAME | TABLE_NAME | JOB_TYPE | SCHEMA_STATE | SCHEMA_ID | TABLE_ID | ROW_COUNT | START_TIME | STATE | +--------+---------+------------+---------------+----------------------+-----------+----------+-----------+-----------------------------------+---------------+ | 45 | test | t1 | add index | write reorganization | 32 | 37 | 0 | 2019-01-10 12:38:36.501 +0800 CST | running | | 44 | test | t1 | add index | none | 32 | 37 | 0 | 2019-01-10 12:36:55.18 +0800 CST | rollback done | | 43 | test | t1 | add index | public | 32 | 37 | 6 | 2019-01-10 12:35:13.66 +0800 CST | synced | | 42 | test | t1 | drop index | none | 32 | 37 | 0 | 2019-01-10 12:34:35.204 +0800 CST | synced | | 41 | test | t1 | add index | public | 32 | 37 | 0 | 2019-01-10 12:33:22.62 +0800 CST | synced | | 40 | test | t1 | drop column | none | 32 | 37 | 0 | 2019-01-10 12:33:08.212 +0800 CST | synced | | 39 | test | t1 | add column | public | 32 | 37 | 0 | 2019-01-10 12:32:55.42 +0800 CST | synced | | 38 | test | t1 | create table | public | 32 | 37 | 0 | 2019-01-10 12:32:41.956 +0800 CST | synced | | 36 | test | | drop table | none | 32 | 34 | 0 | 2019-01-10 11:29:59.982 +0800 CST | synced | | 35 | test | | create table | public | 32 | 34 | 0 | 2019-01-10 11:29:40.741 +0800 CST | synced | | 33 | test | | create schema | public | 32 | 0 | 0 | 2019-01-10 11:29:22.813 +0800 CST | synced | +--------+---------+------------+---------------+----------------------+-----------+----------+-----------+-----------------------------------+---------------+
JOB_ID: each DDL operation corresponds to one DDL job.
JOB_IDis globally unique.
DB_NAME: the name of the database on which the DDL operations are performed.
TABLE_NAME: the name of the table on which the DDL operations are performed.
JOB_TYPE: the type of the DDL operations.
SCHEMA_STATE: the current state of the schema. If the
add index, it is the state of the index; if the
add column, it is the state of the column; if the
create table, it is the state of the table. The common states include:
none: it indicates not existing. When the
createoperation fails and rolls back, it usually becomes the
write reorganization: these four states are intermediate states. For details, see the paper Online, Asynchronous Schema Change in F1. These states are not visible in common operations, because the conversion from the intermediate states is so quick. You can see the
write reorganizationstate only in
add indexoperations, which means that the index data is being added.
public: it indicates existing and usable. When operations like
add index/columnare finished, it usually becomes the
publicstate, which means that the created table/column/index can be normally read and written now.
SCHEMA_ID: the ID of the database on which the DDL operations are performed.
TABLE_ID: the ID of the table on which the DDL operations are performed.
ROW_COUNT: the number of the data rows that have been added when running the
START_TIME: the start time of the DDL operations.
STATE: the state of the DDL operations. The common states include:
none: it indicates that the operation task has been put in the DDL job queue but has not been performed yet, because it is waiting for the previous tasks to complete. Another reason might be that it becomes the
nonestate after running the drop operation, but it will soon be updated to the
syncedstate, which means that all TiDB instances have been synced to this state.
running: it indicates that the operation is being performed.
synced: it indicates that the operation has been performed successfully and all TiDB instances have been synced to this state.
rollback done: it indicates that the operation has failed and has finished rolling back.
rollingback: it indicates that the operation has failed and is rolling back.
cancelling: it indicates that the operation is being cancelled. This state only occurs when you cancel DDL jobs using the
ADMIN CANCEL DDL JOBScommand.
This statement is a TiDB extension to MySQL syntax.