MySQL data type

MySQL supports multiple types and can be broadly divided into three categories: numeric, date/time, and string (character) types.

1). Data Type

Type	Size	Range (signed)	Range (unsigned)	Use
TINYINT	1 bytes	(-128,127)	(0,255)	Small integer value
SMALLINT	2 bytes	(-32 768,32 767)	(0,65 535)	Large integer value
Mediumint	3 bytes	(-8 388 608,8 388 607)	(0,16 777 215)	Large integer value
int or integer	4 bytes	(-2 147 483 648,2 147 483 647)	(0,4 294 967 295)	Large integer value
BIGINT	8 bytes	(-9 233 372 036 854 775 808,9 223 372 036 854 775 807)	(0,18 446 744 073 709 551 615)	Maximum integer value
FLOAT	4 bytes	( -3.402 823 466 e+38,-1.175 494 351 E-38), 0, (1.175 494 351 e-38,3.402 823 466 351 e+38)	0, (1.175 494 351 e-38,3.402 823 466 e+38)	Single precision Floating point value
DOUBLE	8 bytes	( -1.797 693 134 862 315 7 e+308,-2.225 073 858 507 201 4 E-308), 0, (2.225 073 858 507 201 4 e-308,1.797 693 134 862 315 7 E +308)	0, (2.225 073 858 507 201 4 e-308,1.797 693 134 862 315 7 e+308)	Double precision Floating point value
DECIMAL	For decimal (m,d), if m>d, is m+2 otherwise d+2	Values that depend on M and D	Values that depend on M and D	Decimal value

2). Date Type

the date and time type that represents the time value is DATETIME, DATE, TIMESTAMP, Time, and year.

each time type has a valid value range and a value of "0", and a value of "0" is used when specifying an illegal MySQL value that cannot be represented.

Type	Size bytes	Range	Format	Use
DATE	3	1000-01-01/9999-12-31	Yyyy-mm-dd	Date value
Time	3	' -838:59:59 '/' 838:59:59 '	HH:MM:SS	Time Value or duration
Year	1	1901/2155	YYYY	Year value
Datetime	8	1000-01-01 00:00:00/9999-12-31 23:59:59	YYYY-MM-DD HH:MM:SS	Blend date and time values
TIMESTAMP	4	1970-01-01 00:00:00/2038 End time is 2147483647 second, Beijing time 2038-1-19 11:14:07, GMT January 19, 2038 03:14:07	YYYYMMDD HHMMSS	Mixed date and time values, timestamp

3). String Type

String type refers to CHAR, VARCHAR, BINARY, VARBINARY, BLOB, TEXT, enum, and set. This section describes how these types work and how they are used in queries.

Type	Size	Use
CHAR	0-255 bytes	Fixed length string
VARCHAR	0-65535 bytes	Variable length string
Tinyblob	0-255 bytes	A binary string of no more than 255 characters
Tinytext	0-255 bytes	Short text string
Blob	0-65 535 bytes	Long text data in binary form
TEXT	0-65 535 bytes	Long Text data
Mediumblob	0-16 777 215 bytes	Medium-length text data in binary form
Mediumtext	0-16 777 215 bytes	Medium-Length text data
Longblob	0-4 294 967 295 bytes	Large text data in binary form
Longtext	0-4 294 967 295 bytes	Maximum text data

CHAR and VARCHAR types are similar, but they are saved and retrieved in different ways. They are also different in terms of their maximum length and whether trailing spaces are retained. No case conversions are made during the storage or retrieval process.

Binary and VARBINARY are similar to CHAR and VARCHAR, but differ in that they contain binary strings rather than binary strings. That is, they contain a byte string instead of a character string. This means that they do not have a character set, and sort and compare numeric values based on column-valued bytes.

A BLOB is a binary large object that can hold a variable amount of data. There are 4 types of blobs: Tinyblob, BLOBs, Mediumblob, and Longblob. The difference is that they can accommodate different storage ranges.

There are 4 types of text: Tinytext, text, Mediumtext, and Longtext. The corresponding 4 types of blobs, the maximum length can be stored in different, can be selected according to the actual situation.

MySQL data type