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CREATE TABLE | TiDB SQL Statement Reference
An overview of the usage of CREATE TABLE for the TiDB database.
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CREATE TABLE

This statement creates a new table in the currently selected database. See also CREATE TABLE LIKE, which is documented separately.

Synopsis

CreateTableStmt:

CreateTableStmt

IfNotExists:

IfNotExists

TableName:

TableName

TableElementListOpt:

TableElementListOpt

TableElement:

TableElement

PartitionOpt:

PartitionOpt

ColumnDef:

ColumnDef

ColumnName:

ColumnName

Type:

Type

ColumnOptionListOpt:

ColumnOptionListOpt

TableOptionListOpt:

TableOptionListOpt

Syntax

The CREATE TABLE statement is used to create a table. Currently, it does not support temporary tables, CHECK constraints, or importing data from other tables while creating tables. It supports some of the Partition_options in syntax.

Here are some options about the CREATE TABLE syntax:

CREATE TABLE [IF NOT EXISTS] tbl_name
    (create_definition,...)
    [table_options]

When you create an existing table, if you specify IF NOT EXIST, it does not report an error. Otherwise, it reports an error.

CREATE TABLE [IF NOT EXISTS] tbl_name
    { LIKE old_tbl_name | (LIKE old_tbl_name) }

Use LIKE to create an empty table based on the definition of another table including its column and index properties.

create_definition:
    col_name column_definition
  | [CONSTRAINT [symbol]] PRIMARY KEY [index_type] (index_col_name,...)
      [index_option] ...
  | {INDEX|KEY} [index_name] [index_type] (index_col_name,...)
      [index_option] ...
  | [CONSTRAINT [symbol]] UNIQUE [INDEX|KEY]
      [index_name] [index_type] (index_col_name,...)
      [index_option] ...
  | {FULLTEXT} [INDEX|KEY] [index_name] (index_col_name,...)
      [index_option] ...
  | [CONSTRAINT [symbol]] FOREIGN KEY
      [index_name] (index_col_name,...) reference_definition

The FULLTEXT and FOREIGN KEY in create_definition are currently only supported in syntax.

column_definition:
    data_type [NOT NULL | NULL] [DEFAULT default_value]
      [AUTO_INCREMENT | AUTO_RANDOM [(length)]]
      [UNIQUE [KEY] | [PRIMARY] KEY]
      [COMMENT 'string']
      [reference_definition]
  | data_type [GENERATED ALWAYS] AS (expression)
      [VIRTUAL | STORED] [UNIQUE [KEY]] [COMMENT comment]
      [NOT NULL | NULL] [[PRIMARY] KEY]

data_type:
    BIT[(length)]
  | TINYINT[(length)] [UNSIGNED] [ZEROFILL]
  | SMALLINT[(length)] [UNSIGNED] [ZEROFILL]
  | MEDIUMINT[(length)] [UNSIGNED] [ZEROFILL]
  | INT[(length)] [UNSIGNED] [ZEROFILL]
  | INTEGER[(length)] [UNSIGNED] [ZEROFILL]
  | BIGINT[(length)] [UNSIGNED] [ZEROFILL]
  | REAL[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | DOUBLE[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | FLOAT[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | DECIMAL[(length[,decimals])] [UNSIGNED] [ZEROFILL]
  | NUMERIC[(length[,decimals])] [UNSIGNED] [ZEROFILL]
  | DATE
  | TIME[(fsp)]
  | TIMESTAMP[(fsp)]
  | DATETIME[(fsp)]
  | YEAR
  | CHAR[(length)] [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | VARCHAR(length) [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | BINARY[(length)]
  | VARBINARY(length)
  | TINYBLOB
  | BLOB
  | MEDIUMBLOB
  | LONGBLOB
  | TINYTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | TEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | MEDIUMTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | LONGTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | ENUM(value1,value2,value3,...)
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | SET(value1,value2,value3,...)
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | JSON

For the data_type, see Data Types.

index_col_name:
    col_name [(length)] [ASC | DESC]

The [ASC | DESC] in index_col_name is currently only supported in syntax.

index_type:
    USING {BTREE | HASH}

The index_type is currently only supported in syntax.

index_option:
    KEY_BLOCK_SIZE [=] value
  | index_type
  | COMMENT 'string'

The KEY_BLOCK_SIZE in index_option is currently only supported in syntax.

reference_definition:
    REFERENCES tbl_name (index_col_name,...)
      [MATCH FULL | MATCH PARTIAL | MATCH SIMPLE]
      [ON DELETE reference_option]
      [ON UPDATE reference_option]

reference_option:
    RESTRICT | CASCADE | SET NULL | NO ACTION | SET DEFAULT
table_options:
    table_option [[,] table_option] ...

table_option:
    AUTO_INCREMENT [=] value
  | AVG_ROW_LENGTH [=] value
  | SHARD_ROW_ID_BITS [=] value
  | PRE_SPLIT_REGIONS [=] value
  | [DEFAULT] CHARACTER SET [=] charset_name
  | CHECKSUM [=] {0 | 1}
  | [DEFAULT] COLLATE [=] collation_name
  | COMMENT [=] 'string'
  | COMPRESSION [=] {'ZLIB'|'LZ4'|'NONE'}
  | CONNECTION [=] 'connect_string'
  | DELAY_KEY_WRITE [=] {0 | 1}
  | ENGINE [=] engine_name
  | KEY_BLOCK_SIZE [=] value
  | MAX_ROWS [=] value
  | MIN_ROWS [=] value
  | ROW_FORMAT [=] {DEFAULT|DYNAMIC|FIXED|COMPRESSED|REDUNDANT|COMPACT}
  | STATS_PERSISTENT [=] {DEFAULT|0|1}

The table_option currently only supports AUTO_INCREMENT, SHARD_ROW_ID_BITS (see TiDB Specific System Variables for details), PRE_SPLIT_REGIONS, CHARACTER SET, COLLATE, and COMMENT, while the others are only supported in syntax. The clauses are separated by a comma ,. See the following table for details:

Parameters 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
CHARACTER SET To specify the string code for the table; currently only support UTF8MB4 CHARACTER SET = 'utf8mb4'
COMMENT The comment information COMMENT = 'comment info'

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

Examples

mysql> CREATE TABLE t1 (a int);
Query OK, 0 rows affected (0.11 sec)

mysql> CREATE TABLE t2 LIKE t1;
Query OK, 0 rows affected (0.10 sec)

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

mysql> INSERT INTO t1 VALUES (1);
Query OK, 1 row affected (0.02 sec)

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

MySQL compatibility

  • TiDB does not support the syntax CREATE TEMPORARY TABLE.
  • All of the data types except spatial types are supported.
  • FULLTEXT, HASH and SPATIAL indexes are not supported.
  • The KEY_BLOCK_SIZE and ENGINE attributes are parsed but ignored.
  • The index_col_name attribute supports the length option with a maximum length limit of 3072 bytes. The length limit does not change depending on the storage engine, and character set used when building the table.
  • The index_col_name attribute supports the index sorting options of ASC and DESC
  • 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.

See also