The INNODB_SYS_TABLESPACES table provides
metadata about InnoDB tablespaces, equivalent
to the information in the SYS_TABLESPACES table
in the InnoDB data dictionary.
For related usage information and examples, see Section 14.15.3, “InnoDB INFORMATION_SCHEMA System Tables”.
Table 21.24 INNODB_SYS_TABLESPACES Columns
| Column name | Description |
|---|---|
SPACE | Tablespace Space ID. |
NAME | The database and table name (for example,
world_innodb\city) |
FLAG | This value provides bit level information about tablespace format and storage characteristics. |
FILE_FORMAT | The tablespace file format (for example,
Antelope or
Barracuda). The data
in this field is interpreted from the tablespace flags
information that resides in the
.ibd file. For more
information about InnoDB file formats,
see Section 14.10, “InnoDB File-Format Management”. |
ROW_FORMAT | The tablespace row format (Compact or Redundant, Dynamic, or Compressed). The data in this field is interpreted from the tablespace flags information that resides in the .ibd file. |
PAGE_SIZE | The tablespace page size. The data in this field is interpreted from the tablespace flags information that resides in the .ibd file. |
ZIP_PAGE_SIZE | The tablespace zip page size. The data in this field is interpreted from the tablespace flags information that resides in the .ibd file. |
Example:
mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES WHERE SPACE = 57\G
*************************** 1. row ***************************
SPACE: 57
NAME: test/t1
FLAG: 0
FILE_FORMAT: Antelope
ROW_FORMAT: Compact or Redundant
PAGE_SIZE: 16384
ZIP_PAGE_SIZE: 0
Notes:
Use DESCRIBE or
SHOW COLUMNS to view additional
information about the columns of this table including data
types and default values.
You must have the PROCESS
privilege to query this table.
Because tablespace flags are always zero for all Antelope file
formats (unlike table flags), there is no way to determine
from this flag integer if the tablespace row format is
Redundant or Compact. As a result, the possible values for the
ROW_FORMAT field are “Compact or
Redundant”, “Compressed”, or
“Dynamic.”
Interpreting the INNODB_SYS_TABLESPACES.FLAG Column Value:
The INNODB_SYS_TABLESPACES.FLAG column provides
bit-level information about tablespace format and storage
characteristics.
Until MySQL 5.6, table and tablespace flags were the same except
for the bit position 0 settings. In MySQL 5.6, support was added
for 4K and 8K pages, which required an additional 4 bits to hold
the logical page size. Also in MySQL 5.6, support was added for
the CREATE TABLE and
ALTER TABLE DATA
DIRECTORY clause, which allows file-per-table
tablespaces to be stored in a location outside of the MySQL data
directory. This feature required an additional bit for both table
and tablespace flags, but not at the same position.
You can interpret the tablespace FLAG column
value by adding together the applicable decimal numeric values
that are provided in the following table.
Table 21.25 Bit Position Values for Interpreting INNODB_SYS_TABLESPACES FLAG Column Data
| Bit Position | Description | Decimal Numeric Value |
|---|---|---|
| 0 | This bit is set if the row format of tables in the tablespace is
DYNAMIC or
COMPRESSED. This information can help
you distinguish between Antelope and Barracuda file
formats but not between REDUNDANT and
COMPACT file formats
(DYNAMIC and
COMPRESSED row formats require the
Barracuda file format). If it is a file-per-table
tablespace, you must query
INNODB_SYS_TABLES to determine which of
the two Antelope row formats is used
(REDUNDANT or
COMPACT). |
|
| 1-4 | These four bits contain a small number that represents the compressed
page size (the KEY_BLOCK_SIZE or
“physical block size”) of the tablespace. |
|
| 5 | This bit is set for file-per-table tablespaces if the row format of the
table is DYNAMIC or
COMPRESSED. |
|
| 6-9 | These four bits contain a small number that represents the uncompressed
page size (logical page size) of the tablespace. The
setting is zero if the logical page size is the original
InnoDB default page size of 16K. |
|
| 10 | This bit is set if the DATA DIRECTORY option is used
with CREATE TABLE or
ALTER TABLE. This bit is
set for file-per-table tablespaces that are located in
directories other than the default data directory
(datadir). For these
tables, a
|
|
In the following example, table t1 is created
with innodb_file_per_table=ON,
which creates table t1 in its own tablespace.
When querying INNODB_SYS_TABLESPACES,
we see that the tablespace has a FLAG value of
33. To determine how this value is arrived at, review the bit
values described in the preceding table. Bit 0 has a value of 1
because table t1 uses the
DYNAMIC row format. Bit 5 has a value of 32
because the tablespace is a file-per-table tablespace that uses a
DYNAMIC row format. Bit position 6-9 is 0
because innodb_page_size is set
to the default 16K value. The other bit values are not applicable
and are therefore set to 0. The values for bit position 0 and bit
position 5 add up to a FLAG value of 33.
mysql>use test;Database changed mysql>SHOW VARIABLES LIKE 'innodb_file_per_table';+-----------------------+-------+ | Variable_name | Value | +-----------------------+-------+ | innodb_file_per_table | ON | +-----------------------+-------+ 1 row in set (0.00 sec) mysql>SHOW VARIABLES LIKE 'innodb_page_size';+------------------+-------+ | Variable_name | Value | +------------------+-------+ | innodb_page_size | 16384 | +------------------+-------+ 1 row in set (0.00 sec) mysql>SET GLOBAL innodb_file_format=Barracuda;Query OK, 0 rows affected (0.00 sec) mysql>CREATE TABLE t1 (c1 int) ROW_FORMAT=DYNAMIC;Query OK, 0 rows affected (0.02 sec) mysql>SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES WHERE NAME LIKE 'test/t1'\G*************************** 1. row *************************** SPACE: 75 NAME: test/t1 FLAG: 33 FILE_FORMAT: Barracuda ROW_FORMAT: Dynamic PAGE_SIZE: 16384 ZIP_PAGE_SIZE: 0 1 row in set (0.00 sec)