Shulou(Shulou.com)05/31 Report--

This article mainly introduces the mySQL form size example analysis, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let Xiaobian take you to understand.

This is about the size of the form, not the maximum length of an item of data stored in the table.

PS here gives the length of the blob type in the table. BLOB is a binary large object, a container that can store a large amount of data, and it can hold data of different sizes. A BLOB type is actually a family of types (TinyBlob, Blob, MediumBlob, LongBlob) that are equivalent except for the maximum amount of information stored.

Four BLOB types of MySQL

Type size (in bytes)

TinyBlob maximum 255i

Maximum of 65K for Blob

MediumBlob up to 16m

LongBlob maximum 4G

In practical use, different BLOB types are defined according to the amount of data that needs to be stored.

It is important to note that if the file you store is too large, the performance of the database will degrade a lot.

In the old version of MySQL 3.22, the single table size of MySQL was limited to 4GB, and the storage engine of MySQL at that time was the ISAM storage engine. However, with the advent of the MyISAM storage engine, that is, since MySQL 3.23, the maximum limit for MySQL single tables has been extended to 64PB (official documents show). In other words, from the current technical environment, the MyISAM storage engine single table size limit of MySQL database is no longer determined by the MySQL database itself, but by the file system on the OS of the host.

However, Innodb, one of the most popular storage engines of MySQL, has two strategies for storing data, one is shared tablespace storage, and the other is exclusive tablespace storage.

When using shared tablespace storage, all data in Innodb is stored in a single tablespace, which can be composed of many files, and a table can exist across multiple files, so its size limit is no longer the file size limit, but its own limit. As can be seen from the official documentation of Innodb, the maximum tablespace limit of Innodb is 64TB, that is, the single table limit of Innodb is basically around 64TB, of course, this size includes all indexes of this table and other related data.

When exclusive tablespaces are used to store Innodb tables, the data of each table is stored in a separate file, so the single table limit becomes the size limit of the file system.

Here is a little bit of information collected, but not all of it is accurate:

Operating system size limit

Win32 w/ FAT/FAT32 2GB/4GB

Win32 w / NTFS 2TB (maybe larger)

2.2-Intel 32-bit 2GB (LFS: 4GB)

Linux 2.4 + 4TB (ext3)

Solaris 9/10 16TB

NetWare w/NSS filesystem 8TB

MacOS X w/ HFS+ 2TB

The following is what is in the MySQL document:

Please note to Windows users: FAT and VFAT (FAT32) are not suitable for MySQL production. NTFS should be used.

By default, the maximum size allowed for MyISAM created by MySQL is 4GB. You can use the SHOW TABLE STATUS statement or myisamchk-dv tbl_name to check the maximum size of the table. See Section 13.5.4, "SHOW Grammar".

If you need to use MyISAM tables larger than 4GB (and your operating system supports large files), use CREATE TABLE statements that allow AVG_ROW_LENGTH and MAX_ROWS options. After you create the table, you can also use ALTER TABLE to change these options to increase the maximum allowable capacity of the table.

This is about the size of the form, not the maximum length of an item of data stored in the table.

PS here gives the length of the blob type in the table. BLOB is a binary large object, a container that can store a large amount of data, and it can hold data of different sizes. A BLOB type is actually a family of types (TinyBlob, Blob, MediumBlob, LongBlob) that are equivalent except for the maximum amount of information stored.

Four BLOB types of MySQL

Type size (in bytes)

TinyBlob maximum 255i

Maximum of 65K for Blob

MediumBlob up to 16m

LongBlob maximum 4G

In practical use, different BLOB types are defined according to the amount of data that needs to be stored.

It is important to note that if the file you store is too large, the performance will degrade a lot.

The original text is here: http://www.2cto.com/database/201111/111978.html

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This is about the size of the form, not the maximum length of an item of data stored in the table.

PS here gives the length of the blob type in the table. BLOB is a binary large object, a container that can store a large amount of data, and it can hold data of different sizes. A BLOB type is actually a family of types (TinyBlob, Blob, MediumBlob, LongBlob) that are equivalent except for the maximum amount of information stored.

Four BLOB types of MySQL www.2cto.com

Type size (in bytes)

TinyBlob maximum 255i

Maximum of 65K for Blob

MediumBlob up to 16m

LongBlob maximum 4G

In practical use, different BLOB types are defined according to the amount of data that needs to be stored.

It is important to note that if the file you store is too large, the performance of the database will degrade a lot.

Thank you for reading this article carefully. I hope the article "sample Analysis of mySQL form size" shared by the editor will be helpful to you. At the same time, I also hope you will support us and pay attention to the industry information channel. More related knowledge is waiting for you to learn!

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