MySQL Common Data Types

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MySQL Data Types
TYPE
SIZE
DESCRIPTION
CHAR[Length]
Length bytes
A fixed-length field from 0 to 255 characters long
VARCHAR[Length]
String length + 1 bytes
A variable-length field from 0 to 255 characters long
TINYTEXT
String length + 1 bytes
A string with a maximum length of 255 characters
TEXT
String length + 2 bytes
A string with a maximum length of 65,535 characters
MEDIUMTEXT
String length + 3 bytes
A string with a maximum length of 16,777,215 characters
LONGTEXT
String length + 4 bytes
A string with a maximum length of 4,294,967,295 characters
TINYINT[Length]
1 byte
Range of 128 to 127 or 0 to 255 unsigned
SMALLINT[Length]
2 bytes
Range of 32,768 to 32,767 or 0 to 65,535 unsigned
MEDIUMINT[Length]
3 bytes
Range of 8,388,608 to 8,388,607 or 0 to 16,777,215 unsigned
INT[Length]
4 bytes
Range of 2,147,483,648 to 2,147,483,647 or 0 to 4,294,967,295 unsigned
BIGINT[Length]
8 bytes
Range of 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 or 0 to 18,446,744,073,709,551,615 unsigned
FLOAT
4 bytes
A small number with a floating decimal point
DOUBLE[Length, Decimals]
8 bytes
A large number with a floating decimal point
DECIMAL[Length, Decimals]
Length + 1 or Length + 2 bytes
A DOUBLE stored as a string, allowing for a fixed decimal point
DATE
3 bytes
In the format of YYYY-MM-DD
DATETIME
8 bytes
In the format of YYYY-MM-DD HH:MM:SS
TIMESTAMP
4 bytes
In the format of YYYYMMDDHHMMSS; acceptable range ends in the year 2037
TIME
3 bytes
In the format of HH:MM:SS
ENUM
1 or 2 bytes
Short for enumeration, which means that each column can have one of several possible values
SET
1, 2, 3, 4, or 8 bytes
Like ENUM except that each column can have more than one of several possible values


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