The effective maximum table size for MySQL databases is usually determined by operating system constraints on file sizes, not by MySQL internal limits. The following table lists some examples of operating system file-size limits. This is only a rough guide and is not intended to be definitive. For the most up-to-date information, be sure to check the documentation specific to your operating system.
Operating System | File-size Limit |
---|---|
Win32 w/ FAT/FAT32 | 2GB/4GB |
Win32 w/ NTFS | 2TB (possibly larger) |
Linux 2.2-Intel 32-bit | 2GB (LFS: 4GB) |
Linux 2.4+ | (using ext3 file system) 4TB |
Solaris 9/10 | 16TB |
MacOS X w/ HFS+ | 2TB |
Windows users, please note that FAT and VFAT (FAT32) are not considered suitable for production use with MySQL. Use NTFS instead.
On Linux 2.2, you can get MyISAM
tables
larger than 2GB in size by using the Large File Support (LFS)
patch for the ext2 file system. Most current Linux
distributions are based on kernel 2.4 or higher and include
all the required LFS patches. On Linux 2.4, patches also exist
for ReiserFS to get support for big files (up to 2TB). With
JFS and XFS, petabyte and larger files are possible on Linux.
For a detailed overview about LFS in Linux, have a look at Andreas Jaeger's Large File Support in Linux page at http://www.suse.de/~aj/linux_lfs.html.
If you do encounter a full-table error, there are several reasons why it might have occurred:
The
InnoDB
storage engine maintainsInnoDB
tables within a tablespace that can be created from several files. This enables a table to exceed the maximum individual file size. The tablespace can include raw disk partitions, which permits extremely large tables. The maximum tablespace size is 64TB.If you are using
InnoDB
tables and run out of room in theInnoDB
tablespace. In this case, the solution is to extend theInnoDB
tablespace. See Section 13.6.6, “Adding, Removing, or ResizingInnoDB
Data and Log Files”.You are using
MyISAM
tables on an operating system that supports files only up to 2GB in size and you have hit this limit for the data file or index file.You are using a
MyISAM
table and the space required for the table exceeds what is permitted by the internal pointer size.MyISAM
permits data and index files to grow up to 256TB by default, but this limit can be changed up to the maximum permissible size of 65,536TB (2567 – 1 bytes).If you need a
MyISAM
table that is larger than the default limit and your operating system supports large files, theCREATE TABLE
statement supportsAVG_ROW_LENGTH
andMAX_ROWS
options. See Section 12.1.14, “CREATE TABLE
Syntax”. The server uses these options to determine how large a table to permit.If the pointer size is too small for an existing table, you can change the options with
ALTER TABLE
to increase a table's maximum permissible size. See Section 12.1.6, “ALTER TABLE
Syntax”.ALTER TABLE
tbl_name
MAX_ROWS=1000000000 AVG_ROW_LENGTH=nnn
;You have to specify
AVG_ROW_LENGTH
only for tables withBLOB
orTEXT
columns; in this case, MySQL can't optimize the space required based only on the number of rows.To change the default size limit for
MyISAM
tables, set themyisam_data_pointer_size
, which sets the number of bytes used for internal row pointers. The value is used to set the pointer size for new tables if you do not specify theMAX_ROWS
option. The value ofmyisam_data_pointer_size
can be from 2 to 7. A value of 4 permits tables up to 4GB; a value of 6 permits tables up to 256TB.You can check the maximum data and index sizes by using this statement:
SHOW TABLE STATUS FROM
db_name
LIKE 'tbl_name
';You also can use myisamchk -dv /path/to/table-index-file. See Section 12.4.5, “
SHOW
Syntax”, or Section 4.6.3, “myisamchk — MyISAM Table-Maintenance Utility”.Other ways to work around file-size limits for
MyISAM
tables are as follows:If your large table is read only, you can use myisampack to compress it. myisampack usually compresses a table by at least 50%, so you can have, in effect, much bigger tables. myisampack also can merge multiple tables into a single table. See Section 4.6.5, “myisampack — Generate Compressed, Read-Only MyISAM Tables”.
MySQL includes a
MERGE
library that enables you to handle a collection ofMyISAM
tables that have identical structure as a singleMERGE
table. See Section 13.8, “TheMERGE
Storage Engine”.
You are using the
MEMORY
(HEAP
) storage engine; in this case you need to increase the value of themax_heap_table_size
system variable. See Section 5.1.4, “Server System Variables”.