Numeric Data
Integers
Required Storage and Range for Integer Types Supported by MySQL
| Type | Storage (Bytes) | Minimum Value Signed | Minimum Value Unsigned | Maximum Value Signed | Maximum Value Unsigned |
|---|---|---|---|---|---|
| TINYINT | 1 | -128 | 0 | 127 | 255 |
| SMALLINT | 2 | -32768 | 0 | 32767 | 65535 |
| MEDIUMINT | 3 | -8388608 | 0 | 8388607 | 16777215 |
| INT | 4 | -2147483648 | 0 | 2147483647 | 4294967295 |
| BIGINT | 8 | -263 | 0 | 263-1 | 264-1 |
Decimals (money)
salary DECIMAL(5,2)
This means the the salary field has a maximum of 5 numbers with a maximum of 2 numbers after the decimal point.
So values that can be stored in the salary column range from -999.99 to 999.99.
Floats/ Doubles (scientific)
- float uses 4 bytes
- double uses 8 bytes
- these approximate numbers
- carefule when doing approximations
Date types
The following are the form that the date datatype would look like.
| Data Type | “Zero” Value |
|---|---|
| DATE | '0000-00-00' |
| TIME | '00:00:00' |
| DATETIME | '0000-00-00 00:00:00' |
| TIMESTAMP | '0000-00-00 00:00:00' |
| YEAR | 0000 |
String types
- varchar(N)
- text
- tinytext
- text
- mediumtext
- longtext
- blob
- tinyblob
- blob
- mediumblob
- longblob