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HomeDatabaseMysql Tutorial我的MYSQL学习心得(四)_MySQL

我的MYSQL学习心得(四)

MYSQL里的BLOB数据类型

BLOB是一个二进制大对象,用来存储可变数量的数据。BLOB类型分为4种:TinyBlob、Blob、MediumBlob、LongBlob,

这几个类型之间的唯一区别是在存储文件的最大大小上不同。

 

MySQL的四种BLOB类型     类型 大小(单位:字节)

TinyBlob                            最大 255
Blob                                  最大 65K
MediumBlob                       最大 16M
LongBlob                           最大 4G

 

BLOB列存储的是二进制字符串(字节字符串);TEXT列存储的是非二进制字符串(字符字符串)。

BLOB列没有字符集,并且排序和比较基于列值字节的数值;TEXT列有一个字符集,并且根据字符集对值进行排序和比较


SQLSERVER

SQLSERVER并没有BLOB数据类型,只有大型对象数据类型(BLOB):

text,ntext,image,nvarchar(max),varchar(max),varbinary(max)和xml数据类型

这些数据类型的数据都存放在LOB类型的数据页面里

 

如有不对的地方,欢迎大家拍砖o(∩_∩)o 

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