MySQL :: MySQL 5.7 Reference Manual :: 13.1.19 CREATE TABLESPACE Statement (original) (raw)

13.1.19 CREATE TABLESPACE Statement

CREATE TABLESPACE tablespace_name

  InnoDB and NDB:
    ADD DATAFILE 'file_name'

  InnoDB only:
    [FILE_BLOCK_SIZE = value]

  NDB only:
    USE LOGFILE GROUP logfile_group
    [EXTENT_SIZE [=] extent_size]
    [INITIAL_SIZE [=] initial_size]
    [AUTOEXTEND_SIZE [=] autoextend_size]
    [MAX_SIZE [=] max_size]
    [NODEGROUP [=] nodegroup_id]
    [WAIT]
    [COMMENT [=] 'string']

  InnoDB and NDB:
    [ENGINE [=] engine_name]

This statement is used to create a tablespace. The precise syntax and semantics depend on the storage engine used. In standard MySQL 5.7 releases, this is always anInnoDB tablespace. MySQL NDB Cluster 7.5 also supports tablespaces using theNDB storage engine in addition to those using InnoDB.

Considerations for InnoDB

CREATE TABLESPACE syntax is used to create general tablespaces. A general tablespace is a shared tablespace. It can hold multiple tables, and supports all table row formats. General tablespaces can be created in a location relative to or independent of the data directory.

After creating an InnoDB general tablespace, you can use CREATE TABLE tbl_name ... TABLESPACE [=]tablespace_name orALTER TABLE_tbl_name_ TABLESPACE [=]tablespace_name to add tables to the tablespace. For more information, seeSection 14.6.3.3, “General Tablespaces”.

Considerations for NDB Cluster

This statement is used to create a tablespace, which can contain one or more data files, providing storage space for NDB Cluster Disk Data tables (see Section 21.6.11, “NDB Cluster Disk Data Tables”). One data file is created and added to the tablespace using this statement. Additional data files may be added to the tablespace by using the ALTER TABLESPACE statement (see Section 13.1.9, “ALTER TABLESPACE Statement”).

Note

All NDB Cluster Disk Data objects share the same namespace. This means that each Disk Data object must be uniquely named (and not merely each Disk Data object of a given type). For example, you cannot have a tablespace and a log file group with the same name, or a tablespace and a data file with the same name.

A log file group of one or more UNDO log files must be assigned to the tablespace to be created with theUSE LOGFILE GROUP clause.logfilegroup must be an existing log file group created with CREATE LOGFILE GROUP (see Section 13.1.15, “CREATE LOGFILE GROUP Statement”). Multiple tablespaces may use the same log file group forUNDO logging.

When setting EXTENT_SIZE orINITIAL_SIZE, you may optionally follow the number with a one-letter abbreviation for an order of magnitude, similar to those used in my.cnf. Generally, this is one of the letters M (for megabytes) orG (for gigabytes).

INITIAL_SIZE and EXTENT_SIZE are subject to rounding as follows:

Note

NDB reserves 4% of a tablespace for data node restart operations. This reserved space cannot be used for data storage. This restriction applies beginning with NDB 7.6.

The rounding just described is done explicitly, and a warning is issued by the MySQL Server when any such rounding is performed. The rounded values are also used by the NDB kernel for calculating Information Schema FILES column values and other purposes. However, to avoid an unexpected result, we suggest that you always use whole multiples of 32K in specifying these options.

When CREATE TABLESPACE is used withENGINE [=] NDB, a tablespace and associated data file are created on each Cluster data node. You can verify that the data files were created and obtain information about them by querying the Information SchemaFILES table. (See the example later in this section.)

(See Section 24.3.9, “The INFORMATION_SCHEMA FILES Table”.)

Options

Notes

InnoDB Examples

This example demonstrates creating a general tablespace and adding three uncompressed tables of different row formats.

mysql> CREATE TABLESPACE `ts1` ADD DATAFILE 'ts1.ibd' ENGINE=INNODB;

mysql> CREATE TABLE t1 (c1 INT PRIMARY KEY) TABLESPACE ts1 ROW_FORMAT=REDUNDANT;

mysql> CREATE TABLE t2 (c1 INT PRIMARY KEY) TABLESPACE ts1 ROW_FORMAT=COMPACT;

mysql> CREATE TABLE t3 (c1 INT PRIMARY KEY) TABLESPACE ts1 ROW_FORMAT=DYNAMIC;

This example demonstrates creating a general tablespace and adding a compressed table. The example assumes a defaultinnodb_page_size value of 16K. The FILE_BLOCK_SIZE of 8192 requires that the compressed table have a KEY_BLOCK_SIZE of 8.

mysql> CREATE TABLESPACE `ts2` ADD DATAFILE 'ts2.ibd' FILE_BLOCK_SIZE = 8192 Engine=InnoDB;

mysql> CREATE TABLE t4 (c1 INT PRIMARY KEY) TABLESPACE ts2 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8;

NDB Example

Suppose that you wish to create an NDB Cluster Disk Data tablespace named myts using a datafile namedmydata-1.dat. An NDB tablespace always requires the use of a log file group consisting of one or more undo log files. For this example, we first create a log file group named mylg that contains one undo long file named myundo-1.dat, using theCREATE LOGFILE GROUP statement shown here:

mysql> CREATE LOGFILE GROUP myg1
    ->     ADD UNDOFILE 'myundo-1.dat'
    ->     ENGINE=NDB;
Query OK, 0 rows affected (3.29 sec)

Now you can create the tablespace previously described using the following statement:

mysql> CREATE TABLESPACE myts
    ->     ADD DATAFILE 'mydata-1.dat'
    ->     USE LOGFILE GROUP mylg
    ->     ENGINE=NDB;
Query OK, 0 rows affected (2.98 sec)

You can now create a Disk Data table using aCREATE TABLE statement with theTABLESPACE and STORAGE DISK options, similar to what is shown here:

mysql> CREATE TABLE mytable (
    ->     id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
    ->     lname VARCHAR(50) NOT NULL,
    ->     fname VARCHAR(50) NOT NULL,
    ->     dob DATE NOT NULL,
    ->     joined DATE NOT NULL,
    ->     INDEX(last_name, first_name)
    -> )
    ->     TABLESPACE myts STORAGE DISK
    ->     ENGINE=NDB;
Query OK, 0 rows affected (1.41 sec)

It is important to note that only the dob andjoined columns from mytable are actually stored on disk, due to the fact that theid, lname, andfname columns are all indexed.

As mentioned previously, when CREATE TABLESPACE is used with ENGINE [=] NDB, a tablespace and associated data file are created on each NDB Cluster data node. You can verify that the data files were created and obtain information about them by querying the Information SchemaFILES table, as shown here:

mysql> SELECT FILE_NAME, FILE_TYPE, LOGFILE_GROUP_NAME, STATUS, EXTRA
    ->     FROM INFORMATION_SCHEMA.FILES
    ->     WHERE TABLESPACE_NAME = 'myts';

+--------------+------------+--------------------+--------+----------------+
| file_name    | file_type  | logfile_group_name | status | extra          |
+--------------+------------+--------------------+--------+----------------+
| mydata-1.dat | DATAFILE   | mylg               | NORMAL | CLUSTER_NODE=5 |
| mydata-1.dat | DATAFILE   | mylg               | NORMAL | CLUSTER_NODE=6 |
| NULL         | TABLESPACE | mylg               | NORMAL | NULL           |
+--------------+------------+--------------------+--------+----------------+
3 rows in set (0.01 sec)

For additional information and examples, seeSection 21.6.11.1, “NDB Cluster Disk Data Objects”.