Sql Data Types And Operations

SQL Data Types And Operations

SQL Data Types:-

Data types are used to represent the nature of the data that can be stored in the database table. For example, in a particular column of a table, if we want to store a string type of data then we will have to declare a string data type of this column.

Data types mainly classified into three categories for every database.

String Data types

Numeric Data types

Date and time Data types 

SQL Data Type is an attribute that specifies the type of data of any object. Each column, variable and expression has a related data type in SQL. You can use these data types while creating your tables. You can choose a data type for a table column based on your requirement.

SQL Server offers six categories of data types for your use which are listed below −

Exact Numeric Data Types

DATA TYPE	FROM	TO
bigint	-9,223,372,036,854,775,808	9,223,372,036,854,775,807
int	-2,147,483,648	2,147,483,647
smallint	-32,768	32,767
tinyint	0	255
bit	0	1
decimal	-10^38 +1	10^38 -1
numeric	-10^38 +1	10^38 -1
money	-922,337,203,685,477.5808	+922,337,203,685,477.5807
smallmoney	-214,748.3648	+214,748.3647

Approximate Numeric Data Types

DATA TYPE	FROM	TO
float	-1.79E + 308	1.79E + 308
real	-3.40E + 38	3.40E + 38

Date and Time Data Types

DATA TYPE	FROM	TO
datetime	Jan 1, 1753	Dec 31, 9999
smalldatetime	Jan 1, 1900	Jun 6, 2079
date	Stores a date like June 30, 1991
time	Stores a time of day like 12:30 P.M.

Note − Here, datetime has 3.33 milliseconds accuracy where as smalldatetime has 1 minute accuracy.

Character Strings Data Types

Sr.No.	DATA TYPE & Description
1	char Maximum length of 8,000 characters.( Fixed length non-Unicode characters)
2	varchar Maximum of 8,000 characters.(Variable-length non-Unicode data).
3	varchar(max) Maximum length of 2E + 31 characters, Variable-length non-Unicode data (SQL Server 2005 only).
4	text Variable-length non-Unicode data with a maximum length of 2,147,483,647 characters.

Unicode Character Strings Data Types

Sr.No.	DATA TYPE & Description
1	nchar Maximum length of 4,000 characters.( Fixed length Unicode)
2	nvarchar Maximum length of 4,000 characters.(Variable length Unicode)
3	nvarchar(max) Maximum length of 2E + 31 characters (SQL Server 2005 only).( Variable length Unicode)
4	ntext Maximum length of 1,073,741,823 characters. ( Variable length Unicode )

Binary Data Types

Sr.No.	DATA TYPE & Description
1	binary Maximum length of 8,000 bytes(Fixed-length binary data )
2	varbinary Maximum length of 8,000 bytes.(Variable length binary data)
3	varbinary(max) Maximum length of 2E + 31 bytes (SQL Server 2005 only). ( Variable length Binary data)
4	image Maximum length of 2,147,483,647 bytes. ( Variable length Binary Data)

Misc Data Types

Sr.No.	DATA TYPE & Description
1	sql_variant Stores values of various SQL Server-supported data types, except text, ntext, and timestamp.
2	timestamp Stores a database-wide unique number that gets updated every time a row gets updated
3	uniqueidentifier Stores a globally unique identifier (GUID)
4	xml Stores XML data. You can store xml instances in a column or a variable (SQL Server 2005 only).
5	cursor Reference to a cursor object
6	table Stores a result set for later processing

SQL Operators

Every database administrator and user uses SQL queries for manipulating and accessing the data of database tables and views.

The manipulation and retrieving of the data are performed with the help of reserved words and characters, which are used to perform arithmetic operations, logical operations, comparison operations, compound operations, etc.

Operator	Description
+ - * / %	Add Subtract Multiply Divide Modulo

SQL Bitwise Operators

Operator	Description
& | ^	Bitwise ANDSubtract Bitwise OR Bitwise exclusive OR

SQL Comparison Operators

Operator	Description
= > < >= <= <>	Equal to Subtract Greater thanDivide Less than Greater than or equal to Less than or equal to Not equal to-

SQL Compound Operators

Operator	Description
+= -= *= /= %= &= ^-= |*=	Add equals Subtract equals Multiply equals Divide equals Modulo equals Bitwise AND equals Bitwise exclusive equals Bitwise OR equals

SQL Logical Operators

Operator	Description
ALL AND ANY BETWEEN EXISTS IN LIKE NOT OR SOME	TRUE if all of the subquery values meet the condition TRUE if all the conditions separated by AND is TRUE TRUE if any of the subquery values meet the condition TRUE if the operand is within the range of comparisons TRUE if the subquery returns one or more records TRUE if the operand is equal to one of a list of expressions TRUE if the operand matches a pattern Displays a record if the condition(s) is NOT TRUE TRUE if any of the conditions separated by OR is TRUE TRUE if any of the subquery values meet the condition