MySQL data type

Common data types are:

integers: tinyint, smallint, mediumint, int, bigint

Floating point number: float, double

Fixed-point number: decimal

String: char, varchar, tinytext, text, Mediumtext, Longtext

Date: Date, DateTime, timestamp, year, time

How to declare integers:

Type	How to declare
tinyint	tinyint[(m)] [UNSIGNED] [Zerofill] M default is 4
smallint	smallint[(m)] [UNSIGNED] [Zerofill] M default is 6
Mediumint	mediumint[(m)] [UNSIGNED] [Zerofill] M default is 9
Int	int[(m)] [UNSIGNED] [Zerofill] M default is 11
bigint	bigint[(m)] [UNSIGNED] [Zerofill] M default is 20

Note: The m here represents not the exact length stored in the database, but the minimum number of display digits of the int, and the value will not take effect until the Zerofill is specified.

Mysql> CREATE table T (tint(3)); Query OK,0Rows Affected (0.02sec) MySQL> INSERT into T values ( One),(111),(1111); Query OK,3Rows Affected (0.00sec) Records:3Duplicates:0Warnings:0MySQL>Select*From t;+------+| T |+------+| One||111||1111|+------+3RowsinchSet (0.00sec) MySQL> ALTER TABLE t change t tint(3) Zerofill; Query OK,3Rows Affected (0.06sec) Records:3Duplicates:0Warnings:0MySQL>Select*From t;+------+| T |+------+|011||111||1111|+------+3RowsinchSet (0.00Sec

MySQL data type