Basic Mysql Data Type

Type	Size	Description
Char [length]	Length bytes	Fixed Length field, with a length of 0 to bytes
Varchar [length]	String Length + 1 byte	Variable Length field. Before MySQL 65535, the length is 0-bytes. After MySQL, the maximum length is bytes. A UTF-8 character occupies three bytes and a GBK character occupies two bytes.
Tinytext	String Length + 1 byte	String of 0 to bytes
Text	String Length + 2 bytes	String. The maximum length is 0-bytes.
Mediumtext	String Length + 3 bytes	String. The length of a group of bytes is 16777215 bytes.
Longtext	String Length + 4 bytes	String. The maximum length is 4194967295 bytes.
Tinyint [length]	1 byte	Range:-128 ~ 127 or 0 ~ 255
Smallint [length]	2 bytes
Mediumint [length]	3 bytes
Int [length]	4 bytes
Bigint [length]	8 bytes
Float	4 bytes
Double [length, decimals]	8 bytes	Run a fixed decimal point
Decimal [length, decimals]	Length + 1 byte or length + 2 byte
Date	3 bytes	YYYY-MM-DD format
Datetime	8 bytes	YYYY-MM-DD in HH: mm: SS format
Timestamp	4 bytes	Yyyymmddhhmmss format
Time	3 bytes	Hh: mm: SS format
Enum	1 or 2 bytes	Enumeration type
Set	1, 2, 3, 4, or 8 bytes	Like Enum, each column can have multiple possible values.
blob		is a variant of text. Binary files can be stored and used to encrypt data.