Datatype :

MySql has the following datatypes :

Integer Types :

MySQL supports the SQL standard integer types INTEGER (or INT) and SMALLINT. As an extension to the standard, MySQL also supports the integer types TINYINT, MEDIUMINT, and BIGINT. The following table shows the required storage and range for each integer type.

Type Storage
(Bytes) 		Minimum Value
(Signed/Unsigned) 		Maximum Value
(Signed/Unsigned)
TINYINT 1 -128 127
    0 255
SMALLINT 2 -32768 32767
    0 65535
MEDIUMINT 3 -8388608 8388607
    0 16777215
INT 4 -2147483648 2147483647
    0 4294967295
BIGINT 8 -9223372036854775808 9223372036854775807
    0 18446744073709551615

Float Types :

MySQL Datatype Length Default value(if not null)
FLOAT 32 Bit Floating Point 0
DOUBLE 64 Bit Floating Point 0

Char Types :

MySQL Datatype Length Default value(if not null)
CHAR 1 to 255 Characters space
VARCHAR 1 to 255 Characters space

The CHAR and VARCHAR types are declared with a length that indicates the maximum number of characters you want to store. For example, CHAR(30) can hold up to 30 characters.

Difference between CHAR and VARCHAR :

* The CHAR and VARCHAR types are similar, but differ in the way they are stored and retrieved.

* The length of a CHAR column is fixed to the length that you declare when you create the table. The length can be any value from 0 to 255. When CHAR values are stored, they are right-padded with spaces to the specified length. When CHAR values are retrieved, trailing spaces are removed.

* VARCHAR values are not padded when they are stored. Handling of trailing spaces is version-dependent.

Text Types :

MySQL Datatype Length Default value(if not null)
TEXT 1 to 65535 Characters space

Date Types :

MySQL Datatype Length Default value(if not null)
DATE 1 to 4,294,967,295 Bytes 0000-00-00
DATETIME 1 to 4,294,967,295 Bytes 0000-00-00 00:00:00