14.9.1.7 SQL Compression Syntax Warnings and Errors
This section describes syntax warnings and errors that you may encounter when using the table compression feature with file-per-table tablespaces and general tablespaces.
SQL Compression Syntax Warnings and Errors for File-Per-Table Tablespaces
When innodb_strict_mode
is enabled (the default), specifying ROW_FORMAT=COMPRESSED
or KEY_BLOCK_SIZE
in CREATE TABLE
or ALTER TABLE
statements produces the following error if innodb_file_per_table
is disabled or if innodb_file_format
is set to Antelope
rather than Barracuda
.
ERROR 1031 (HY000): Table storage engine for 't1' doesn't have this option
The table is not created if the current configuration does not permit using compressed tables.
When innodb_strict_mode
is disabled, specifying ROW_FORMAT=COMPRESSED
or KEY_BLOCK_SIZE
in CREATE TABLE
or ALTER TABLE
statements produces the following warnings if innodb_file_per_table
is disabled.
mysql> SHOW WARNINGS;
+---------+------+---------------------------------------------------------------+
| Level | Code | Message |
+---------+------+---------------------------------------------------------------+
| Warning | 1478 | InnoDB: KEY_BLOCK_SIZE requires innodb_file_per_table. |
| Warning | 1478 | InnoDB: ignoring KEY_BLOCK_SIZE=4. |
| Warning | 1478 | InnoDB: ROW_FORMAT=COMPRESSED requires innodb_file_per_table. |
| Warning | 1478 | InnoDB: assuming ROW_FORMAT=DYNAMIC. |
+---------+------+---------------------------------------------------------------+
Similar warnings are issued if innodb_file_format
is set to Antelope
rather than Barracuda
.
These messages are only warnings, not errors, and the table is created without compression, as if the options were not specified.
The “non-strict” behavior lets you import a mysqldump
file into a database that does not support compressed tables, even if the source database contained compressed tables. In that case, MySQL creates the table in ROW_FORMAT=COMPACT
instead of preventing the operation.
To import the dump file into a new database, and have the tables re-created as they exist in the original database, ensure the server has the proper settings for the configuration parameters innodb_file_format
and innodb_file_per_table
.
The attribute KEY_BLOCK_SIZE
is permitted only when ROW_FORMAT
is specified as COMPRESSED
or is omitted. Specifying a KEY_BLOCK_SIZE
with any other ROW_FORMAT
generates a warning that you can view with SHOW WARNINGS
. However, the table is non-compressed; the specified KEY_BLOCK_SIZE
is ignored).
Level | Code | Message |
---|---|---|
Warning | 1478 | InnoDB: ignoring KEY_BLOCK_SIZE= |
If you are running with innodb_strict_mode
enabled, the combination of a KEY_BLOCK_SIZE
with any ROW_FORMAT
other than COMPRESSED
generates an error, not a warning, and the table is not created.
Table 14.6, “ROW_FORMAT and KEY_BLOCK_SIZE Options” provides an overview the ROW_FORMAT
and KEY_BLOCK_SIZE
options that are used with CREATE TABLE
or ALTER TABLE
.
Table 14.6 ROW_FORMAT and KEY_BLOCK_SIZE Options
Option | Usage Notes | Description |
---|---|---|
ROW_FORMAT=REDUNDANT |
Storage format used prior to MySQL 5.0.3 | Less efficient than ROW_FORMAT=COMPACT ; for backward compatibility |
ROW_FORMAT=COMPACT |
Default storage format since MySQL 5.0.3 | Stores a prefix of 768 bytes of long column values in the clustered index page, with the remaining bytes stored in an overflow page |
ROW_FORMAT=DYNAMIC |
File-per-table tablespaces require innodb_file_format=Barracuda |
Store values within the clustered index page if they fit; if not, stores only a 20-byte pointer to an overflow page (no prefix) |
ROW_FORMAT=COMPRESSED |
File-per-table tablespaces require innodb_file_format=Barracuda |
Compresses the table and indexes using zlib |
KEY_BLOCK_SIZE= |
File-per-table tablespaces require innodb_file_format=Barracuda |
Specifies compressed page size of 1, 2, 4, 8 or 16 kilobytes; implies ROW_FORMAT=COMPRESSED . For general tablespaces, a KEY_BLOCK_SIZE value equal to the InnoDB page size is not permitted. |
Table 14.7, “CREATE/ALTER TABLE Warnings and Errors when InnoDB Strict Mode is OFF” summarizes error conditions that occur with certain combinations of configuration parameters and options on the CREATE TABLE
or ALTER TABLE
statements, and how the options appear in the output of SHOW TABLE STATUS
.
When innodb_strict_mode
is OFF
, MySQL creates or alters the table, but ignores certain settings as shown below. You can see the warning messages in the MySQL error log. When innodb_strict_mode
is ON
, these specified combinations of options generate errors, and the table is not created or altered. To see the full description of the error condition, issue the SHOW ERRORS
statement: example:
mysql>CREATE TABLE x (id INT PRIMARY KEY, c INT)
->ENGINE=INNODB KEY_BLOCK_SIZE=33333;
ERROR 1005 (HY000): Can't create table 'test.x' (errno: 1478) mysql>SHOW ERRORS;
+-------+------+-------------------------------------------+ | Level | Code | Message | +-------+------+-------------------------------------------+ | Error | 1478 | InnoDB: invalid KEY_BLOCK_SIZE=33333. | | Error | 1005 | Can't create table 'test.x' (errno: 1478) | +-------+------+-------------------------------------------+
Table 14.7 CREATE/ALTER TABLE Warnings and Errors when InnoDB Strict Mode is OFF
Syntax | Warning or Error Condition | Resulting ROW_FORMAT , as shown in SHOW TABLE STATUS |
---|---|---|
ROW_FORMAT=REDUNDANT |
None | REDUNDANT |
ROW_FORMAT=COMPACT |
None | COMPACT |
ROW_FORMAT=COMPRESSED or ROW_FORMAT=DYNAMIC or KEY_BLOCK_SIZE is specified |
Ignored for file-per-table tablespaces unless both innodb_file_format =Barracuda and innodb_file_per_table are enabled. General tablespaces support all row formats (with some restrictions) regardless of innodb_file_format and innodb_file_per_table settings. See Section 14.6.3.3, “General Tablespaces”. |
the default row format for file-per-table tablespaces; the specified row format for general tablespaces |
Invalid KEY_BLOCK_SIZE is specified (not 1, 2, 4, 8 or 16) |
KEY_BLOCK_SIZE is ignored |
the specified row format, or the default row format |
ROW_FORMAT=COMPRESSED and valid KEY_BLOCK_SIZE are specified |
None; KEY_BLOCK_SIZE specified is used |
COMPRESSED |
KEY_BLOCK_SIZE is specified with REDUNDANT , COMPACT or DYNAMIC row format |
KEY_BLOCK_SIZE is ignored |
REDUNDANT , COMPACT or DYNAMIC |
ROW_FORMAT is not one of REDUNDANT , COMPACT , DYNAMIC or COMPRESSED |
Ignored if recognized by the MySQL parser. Otherwise, an error is issued. | the default row format or N/A |
When innodb_strict_mode
is ON
, MySQL rejects invalid ROW_FORMAT
or KEY_BLOCK_SIZE
parameters and issues errors. When innodb_strict_mode
is OFF
, MySQL issues warnings instead of errors for ignored invalid parameters. innodb_strict_mode
is ON
by default.
When innodb_strict_mode
is ON
, MySQL rejects invalid ROW_FORMAT
or KEY_BLOCK_SIZE
parameters. For compatibility with earlier versions of MySQL, strict mode is not enabled by default; instead, MySQL issues warnings (not errors) for ignored invalid parameters.
It is not possible to see the chosen KEY_BLOCK_SIZE
using SHOW TABLE STATUS
. The statement SHOW CREATE TABLE
displays the KEY_BLOCK_SIZE
(even if it was ignored when creating the table). The real compressed page size of the table cannot be displayed by MySQL.
SQL Compression Syntax Warnings and Errors for General Tablespaces
If
FILE_BLOCK_SIZE
was not defined for the general tablespace when the tablespace was created, the tablespace cannot contain compressed tables. If you attempt to add a compressed table, an error is returned, as shown in the following example:mysql> CREATE TABLESPACE `ts1` ADD DATAFILE 'ts1.ibd' Engine=InnoDB; mysql> CREATE TABLE t1 (c1 INT PRIMARY KEY) TABLESPACE ts1 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8; ERROR 1478 (HY000): InnoDB: Tablespace `ts1` cannot contain a COMPRESSED table
Attempting to add a table with an invalid
KEY_BLOCK_SIZE
to a general tablespace returns an error, as shown in the following example:mysql> CREATE TABLESPACE `ts2` ADD DATAFILE 'ts2.ibd' FILE_BLOCK_SIZE = 8192 Engine=InnoDB; mysql> CREATE TABLE t2 (c1 INT PRIMARY KEY) TABLESPACE ts2 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=4; ERROR 1478 (HY000): InnoDB: Tablespace `ts2` uses block size 8192 and cannot contain a table with physical page size 4096
For general tablespaces, the
KEY_BLOCK_SIZE
of the table must be equal to theFILE_BLOCK_SIZE
of the tablespace divided by 1024. For example, if theFILE_BLOCK_SIZE
of the tablespace is 8192, theKEY_BLOCK_SIZE
of the table must be 8.Attempting to add a table with an uncompressed row format to a general tablespace configured to store compressed tables returns an error, as shown in the following example:
mysql> CREATE TABLESPACE `ts3` ADD DATAFILE 'ts3.ibd' FILE_BLOCK_SIZE = 8192 Engine=InnoDB; mysql> CREATE TABLE t3 (c1 INT PRIMARY KEY) TABLESPACE ts3 ROW_FORMAT=COMPACT; ERROR 1478 (HY000): InnoDB: Tablespace `ts3` uses block size 8192 and cannot contain a table with physical page size 16384
innodb_strict_mode
is not applicable to general tablespaces. Tablespace management rules for general tablespaces are strictly enforced independently of innodb_strict_mode
. For more information, see Section 13.1.19, “CREATE TABLESPACE Statement”.
For more information about using compressed tables with general tablespaces, see Section 14.6.3.3, “General Tablespaces”.