Page 248 - PYTHON-12

12.12 SQL DATATYPES

Just like any other programming
language, the facility of defining data MySQL Data
types
of various types is available in SQL
also. SQL supports the following
datatypes for the specification of
Non-numeric or
various data-items or fields of a Numeric Date and Time
String
relation/table. In SQL, each column
Fig. 12.19: MySQL Datatypes
of the table is assigned a datatype
which conveys the kind of value that
will be stored in the column.
Datatype Syntax Description
INTEGER (Numeric) INTEGER or It stores/represents positive whole numbers up to 11 digits and
integer negative whole numbers up to 10 digits. The range of integer is from
–2,147,483,648 to 2,147,483,647.
SMALLINT SMALLINT It is a 16-bit signed integer value that stores whole numbers in the range
-32768 to 32767. Its width is up to 5 digits.
NUMERIC NUMERIC(x,y) Numbers are stored in the given format, where x is the total number of
digits and y is the number of places to the right of the decimal point. x must
include an extra place for the decimal point.
For example, Numeric(8,2)
In the given example, numeric datatype stores a number that has 5 places
before the decimal and 2 digits after the decimal and 1 digit place for the
decimal point. Numeric holds up to 20 significant digits. A negative number
holds one place for the sign, i.e., (–).
DECIMAL DECIMAL(x,y) Numbers stored in the DECIMAL format, where x is the size, i.e., total
Or number of digits, and y is precision, i.e., it is the number of places to the
DECIMAL(size, right of the decimal point.
precision)
For example, Decimal(8,2)
In the above example, decimal datatype stores a number that has 6 digits
decimal point before the decimal and 2 digits after the decimal.
Decimal holds up to 19 significant digits. A negative number uses one
place for its sign (–).

Computer Science with Python–XII 12.18 CHARACTER CHAR(x) This datatype stores ‘x’ number of characters in the string which has a fixed

(fixed length)
length. A maximum of 254 characters can be stored in a string. If you store
or
CHAR(size)
strings that are not as long as the ‘size’ or ‘x’ parameter value,the remaining
spaces are left unused. For example, if you specify CHAR(10), strings such
as “ram” and “technology” are each stored as 10 characters. However, a
student admission_no is 6 digits long in a school, so CHAR(6) would be
appropriate to store the admission_no of all the students. This datatype
is suitable where the number of characters to store is fixed. The value for
CHAR data type has to be enclosed in single or double quotation marks.