The differences between BLOB and TEXT

最新推荐文章于 2024-04-20 21:16:14 发布

原创最新推荐文章于 2024-04-20 21:16:14 发布 · 471 阅读

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#types #character #object #each

本文详细介绍了数据库中BLOB与TEXT类型的特性及其差异。BLOB类型包括TINYBLOB、BLOB、MEDIUMBLOB及LONGBLOB，用于存储二进制大数据对象；TEXT类型则包括TINYTEXT、TEXT、MEDIUMTEXT及LONGTEXT，主要用于存储文本数据。两种类型的最大区别在于BLOB不支持字符集而TEXT类型支持。此外，文章还提供了每种类型能存储的最大数据长度。

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A BLOB is a binary large object that can hold a variable amount of data. The four BLOB types are TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB. These differ only in the maximum length of the values they can hold. The four TEXT types are TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT. These correspond to the four BLOB types and have the same maximum lengths and storage requirements.

BLOB doesn't have a character set, but TEXT has.

Keeping in mind the caveats above about max packet size and RAM, here are the sizes of each of the text types:
TINYBLOB, TINYTEXT:
2^8 or 256 bytes
BLOB, TEXT:
2^16 or 65536 bytes (64 kiB)
MEDIUMBLOB, MEDIUMTEXT:
2^24 or 16777216 bytes (16 MiB)
LONGBLOB, LONGTEXT:
2^32 or 4294967296 bytes (4 GiB)

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