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sql-statement-create-table.md

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CREATE TABLE | TiDB SQL Statement Reference
An overview of the usage of CREATE TABLE for the TiDB database.
/docs/dev/sql-statements/sql-statement-create-table/
/docs/dev/reference/sql/statements/create-table/

CREATE TABLE

This statement creates a new table in the currently selected database. It behaves similarly to the CREATE TABLE statement in MySQL.

Synopsis

CreateTableStmt ::=
    'CREATE' OptTemporary 'TABLE' IfNotExists TableName ( TableElementListOpt CreateTableOptionListOpt PartitionOpt DuplicateOpt AsOpt CreateTableSelectOpt | LikeTableWithOrWithoutParen )

IfNotExists ::=
    ('IF' 'NOT' 'EXISTS')?

TableName ::=
    Identifier ('.' Identifier)?

TableElementListOpt ::=
    ( '(' TableElementList ')' )?

TableElementList ::=
    TableElement ( ',' TableElement )*

TableElement ::=
    ColumnDef
|   Constraint

ColumnDef ::=
    ColumnName ( Type | 'SERIAL' ) ColumnOptionListOpt

ColumnOptionListOpt ::=
    ColumnOption*

ColumnOptionList ::=
    ColumnOption*

ColumnOption ::=
    'NOT'? 'NULL'
|   'AUTO_INCREMENT'
|   PrimaryOpt 'KEY'
|   'UNIQUE' 'KEY'?
|   'DEFAULT' DefaultValueExpr
|   'SERIAL' 'DEFAULT' 'VALUE'
|   'ON' 'UPDATE' NowSymOptionFraction
|   'COMMENT' stringLit
|   ConstraintKeywordOpt 'CHECK' '(' Expression ')' EnforcedOrNotOrNotNullOpt
|   GeneratedAlways 'AS' '(' Expression ')' VirtualOrStored
|   ReferDef
|   'COLLATE' CollationName
|   'COLUMN_FORMAT' ColumnFormat
|   'STORAGE' StorageMedia
|   'AUTO_RANDOM' OptFieldLen

CreateTableOptionListOpt ::=
    TableOptionList?

PartitionOpt ::=
    ( 'PARTITION' 'BY' PartitionMethod PartitionNumOpt SubPartitionOpt PartitionDefinitionListOpt )?

DuplicateOpt ::=
    ( 'IGNORE' | 'REPLACE' )?

TableOptionList ::=
    TableOption ( ','? TableOption )*

TableOption ::=
    PartDefOption
|   DefaultKwdOpt ( CharsetKw EqOpt CharsetName | 'COLLATE' EqOpt CollationName )
|   ( 'AUTO_INCREMENT' | 'AUTO_ID_CACHE' | 'AUTO_RANDOM_BASE' | 'AVG_ROW_LENGTH' | 'CHECKSUM' | 'TABLE_CHECKSUM' | 'KEY_BLOCK_SIZE' | 'DELAY_KEY_WRITE' | 'SHARD_ROW_ID_BITS' | 'PRE_SPLIT_REGIONS' ) EqOpt LengthNum
|   ( 'CONNECTION' | 'PASSWORD' | 'COMPRESSION' ) EqOpt stringLit
|   RowFormat
|   ( 'STATS_PERSISTENT' | 'PACK_KEYS' ) EqOpt StatsPersistentVal
|   ( 'STATS_AUTO_RECALC' | 'STATS_SAMPLE_PAGES' ) EqOpt ( LengthNum | 'DEFAULT' )
|   'STORAGE' ( 'MEMORY' | 'DISK' )
|   'SECONDARY_ENGINE' EqOpt ( 'NULL' | StringName )
|   'UNION' EqOpt '(' TableNameListOpt ')'
|   'ENCRYPTION' EqOpt EncryptionOpt

The following table_options are supported. Other options such as AVG_ROW_LENGTH, CHECKSUM, COMPRESSION, CONNECTION, DELAY_KEY_WRITE, ENGINE, KEY_BLOCK_SIZE, MAX_ROWS, MIN_ROWS, ROW_FORMAT and STATS_PERSISTENT are parsed but ignored.

Options Description Example
AUTO_INCREMENT The initial value of the increment field AUTO_INCREMENT = 5
SHARD_ROW_ID_BITS To set the number of bits for the implicit _tidb_rowid shards SHARD_ROW_ID_BITS = 4
PRE_SPLIT_REGIONS To pre-split 2^(PRE_SPLIT_REGIONS) Regions when creating a table PRE_SPLIT_REGIONS = 4
AUTO_ID_CACHE To set the auto ID cache size in a TiDB instance. By default, TiDB automatically changes this size according to allocation speed of auto ID AUTO_ID_CACHE = 200
AUTO_RANDOM_BASE To set the initial incremental part value of auto_random. This option can be considered as a part of the internal interface. Users can ignore this parameter AUTO_RANDOM_BASE = 0
CHARACTER SET To specify the character set for the table CHARACTER SET = 'utf8mb4'
COMMENT The comment information COMMENT = 'comment info'

Note:

The split-table configuration option is enabled by default. When it is enabled, a separate Region is created for each newly created table. For details, see TiDB configuration file.

Examples

Creating a simple table and inserting one row:

{{< copyable "sql" >}}

CREATE TABLE t1 (a int);
DESC t1;
SHOW CREATE TABLE t1\G
INSERT INTO t1 (a) VALUES (1);
SELECT * FROM t1;
mysql> drop table if exists t1;
Query OK, 0 rows affected (0.23 sec)

mysql> CREATE TABLE t1 (a int);
Query OK, 0 rows affected (0.09 sec)

mysql> DESC t1;
+-------+---------+------+------+---------+-------+
| Field | Type    | Null | Key  | Default | Extra |
+-------+---------+------+------+---------+-------+
| a     | int(11) | YES  |      | NULL    |       |
+-------+---------+------+------+---------+-------+
1 row in set (0.00 sec)

mysql> SHOW CREATE TABLE t1\G
*************************** 1. row ***************************
       Table: t1
Create Table: CREATE TABLE `t1` (
  `a` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
1 row in set (0.00 sec)

mysql> INSERT INTO t1 (a) VALUES (1);
Query OK, 1 row affected (0.03 sec)

mysql> SELECT * FROM t1;
+------+
| a    |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

Dropping a table if it exists, and conditionally creating a table if it does not exist:

{{< copyable "sql" >}}

DROP TABLE IF EXISTS t1;
CREATE TABLE IF NOT EXISTS t1 (
 id BIGINT NOT NULL PRIMARY KEY auto_increment,
 b VARCHAR(200) NOT NULL
);
DESC t1;
mysql> DROP TABLE IF EXISTS t1;
Query OK, 0 rows affected (0.22 sec)

mysql> CREATE TABLE IF NOT EXISTS t1 (
    ->  id BIGINT NOT NULL PRIMARY KEY auto_increment,
    ->  b VARCHAR(200) NOT NULL
    -> );
Query OK, 0 rows affected (0.08 sec)

mysql> DESC t1;
+-------+--------------+------+------+---------+----------------+
| Field | Type         | Null | Key  | Default | Extra          |
+-------+--------------+------+------+---------+----------------+
| id    | bigint(20)   | NO   | PRI  | NULL    | auto_increment |
| b     | varchar(200) | NO   |      | NULL    |                |
+-------+--------------+------+------+---------+----------------+
2 rows in set (0.00 sec)

MySQL compatibility

  • TiDB does not support temporary tables. The CREATE TEMPORARY TABLE syntax will raise an error if tidb_enable_noop_functions = 0; TiDB simply ignores the TEMPORARY keyword if tidb_enable_noop_functions = 1.
  • All of the data types except spatial types are supported.
  • FULLTEXT, HASH and SPATIAL indexes are not supported.
  • For compatibility, the index_col_name attribute supports the length option with a maximum length limit of 3072 bytes by default. The length limit can be changed through the max-index-length configuration option. For details, see TiDB configuration file.
  • The [ASC | DESC] in index_col_name is currently parsed but ignored (MySQL 5.7 compatible behavior).
  • The COMMENT attribute supports a maximum of 1024 characters and does not support the WITH PARSER option.
  • TiDB supports at most 512 columns in a single table. The corresponding number limit in InnoDB is 1017, and the hard limit in MySQL is 4096. For details, see TiDB Limitations.
  • For partitioned tables, only Range, Hash and Range Columns (single column) are supported. For details, see partitioned table.
  • CHECK constraints are parsed but ignored (MySQL 5.7 compatible behavior). For details, see Constraints.
  • FOREIGN KEY constraints are parsed and stored, but not enforced by DML statements. For details, see Constraints.

See also