| Data type | Length | Description |
|---|---|---|
| TINYINT | 1 byte | Range from -128 to +127 (unsigned: from 0 to 255) |
| SMALLINT | 2 bytes | Range from -32 768 to +32 767 (unsigned: from 0 to 65 535) |
| MEDIUMINT | 3 bytes | Range from -8 388 608 to +8 388 607 (unsigned: from 0 to 16 777 215) |
| INT,INTEGER | 4 bytes | Range from -2 147 483 648 to +2 147 483 647 (unsigned: from 0 to 4 294 967 295) |
| BIGINT | 8 bytes | Range from -9 223 372 036 854 775 808 to +9 223 372 036 854 775 807 (unsigned: from 0 to 18 446 744 073 709 551 615) |
| BIT, BOOL | 1 byte | synonym for TINYINT(1) type |
| FLOAT | Range from -3.402823466E+38 to +3.402823466E+38 | |
| DOUBLE | Range from -1.7976931348623157E+308 to +1.7976931348623157E+308 | |
| DOUBLE PRECISION, REAL | synonym for DOUBLE type | |
| DECIMAL(m,d), DEC(m,d), NUMERIC(m,d | the range sets the "m" and "d" parameters, the maximum range is the same as for DOUBLE type | |
| DATE | '0000-00-00' | the date in format "year-month-day" meaning "RRRR-MM-DD". Range from 1000-01-01 to 9999-12-31 |
| DATETIME | '0000-00-00 00:00:00' | date and time. Range from 1000-01-01 00:00:00 to 9999-12-31 23:59:59 (format = "RRRR-MM-DD HH:MM:SS") |
| TIMESTAMP(n) | '0000-00-00 00:00:00' |
- date and time in the range from 1970-01-01 00:00:00 to 2037-01-01 00:00:00 (all 14 digits are always stored !)
- the display format can be set by "m" parameter with the value of 14 (or missing), 12, 10, 8, 6, 4, or 2
- "RRRRMMDDHHMMSS", "RRMMDDHHMMSS", "RRMMDDHHMM", "RRRRMMDD", "RRMMDD", "YYMM", "YY"
- if no data is written into such cell then the MySQL will add the current time of modification of the corresponding row |
| TIME | '00:00:00' | time range is from "-838:59:59" to "838:59:59" (format "HH:MM:SS") |
| YEAR(n) | 0000 | YEAR(4) = range from 1901 to 2155, (format "RRRR"), YEAR(2) = range from 1970 to 2069 |
| CHAR(m) |
- the string length "m" can be in the range from 0 to 255
- if the entered string is shorter than defined, then the missing characters are filled automatically with spaces (the length is fixed)
- CHAR (without "m") is considered to be CHAR(1) | |
| VARCHAR(m) |
- the string length "m" can be in the range from 0 to 255
- if the entered string is shorter than defined, then the missing characters are not filled (the length is flexible), but the information about its length is also stored | |
| TINYBLOB, TINYTEXT | String length is max. 255 characters | |
| BLOB, TEXT | String length is max. 65 535 characters | |
| MEDIUMBLOB, MEDIUMTEXT | String length is max. 16 777 215 characters | |
| LONGBLOB, LONGTEXT | String length is max. 4 294 967 295 characters | |
| ENUM('item1','item2',...) |
- array of defined strings (items) of the max. number of 65 535
- the table cell may contain only a single item of the defined set
- instead of using the 'item' name, the item order can also be used: 1 (instead of 'item1'), 2 (instead of 'item2')... | |
| SET('item1','item2',...) |
- array of defined strings (items) with the max. number of 64
- the table cell may contain multiple defined items |