MySQL Field Length

MySQL fields have various types and their lengths are different. The following describes the length of various MySQL fields for your reference.

Value Type
Storage required for column types
TINYINT 1 byte
SMALLINT 2 bytes
MEDIUMINT 3 bytes
INT 4 bytes
INTEGER 4 bytes
BIGINT 8 bytes
FLOAT (X) 4 bytes if X <= 24 or 8 If 25 <= X <= 53)
FLOAT 4 bytes
DOUBLE 8 bytes
Double precision 8 bytes
REAL 8 bytes
DECIMAL (M, D) M bytes D + 2, if M <D)
NUMERIC (M, D) M bytes D + 2, if M <D)

Date and Time Type
Storage required for column types
DATE 3 bytes
DATETIME 8 bytes
TIMESTAMP 4 bytes
TIME 3 bytes
YEAR 1 byte

String type
Storage required for column types
CHAR (M) M bytes, 1 <= M <= 255
VARCHAR (M) L + 1 byte, where L <= M and 1 <= M <= 255
TINYBLOB, tinytext l + 1 byte, here L <2 ^ 8
BLOB, text l + 2 bytes, here L <2 ^ 16
MEDIUMBLOB, mediumtext l + 3 bytes, here L <2 ^ 24
LONGBLOB, longtext l + 4 bytes, here L <2 ^ 32
ENUM ('value1 ', 'value2',...) 1 or 2 bytes, depending on the maximum number of enumeration values 65535)
SET ('value1 ', 'value2',...) 1, 2, 3, 4, or 8 bytes, depending on the maximum number of members in the SET)
 

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