Sql server ___________session 2(sql 2008)

New Features of SQL Server 2008 / Session 2 2
Objectives

Describe the process of declaring variables.

Explain the new data types in SQL Server 2008.

Describe sparse columns.

Explain the concept of wide tables.

Describe spatial data types.

Explain the hierarchyid data type.

Explain the new enhancements in the CONVERT()
function.

Describe the enhancements to date functions.

Explain the new XQuery functions.

Describe compound assignment operators.

Variables and Data Types

Variable represents a location in computer
memory to store data

Data can be of different data types such as
integer, decimal, date, and so on

Declaration and initialization of variables were
done separately in SQL Server 2005

Variable Declaration 1-2

SQL Server 2005
DECLARE @firstname varchar(25)
SET @firstname = 'harry'
Example

SQL Server 2008
Syntax
DECLARE @local_variable [AS] data_type[ = value ]
Example
DECLARE @firstname varchar(25) = 'harry'

Variable Declaration 2-2
--Variable declaration of type int
DECLARE @age int = 40
--Variable declaration of type decimal
DECLARE @taxPercent decimal = 0.75
--Variable declaration of type money
DECLARE @amount money = 50000
DECLARE @bonus money = @amount*.10
--Variable declaration of type date
DECLARE @userDate date = '09-30-2009'
DECLARE @currentDate date = GETDATE()
SELECT @age, @taxPercent, @amount, @bonus,@userDate, @currentDate
Example
The following example shows variable declaration and initialization
for different data types.
Output

New Date and Time Types

datetime and smalldatetime data types stored
the date with time component in SQL Server 2005

In SQL Server 2008, Microsoft introduced new date and
time data types

date

time
 datetme2

datetimeoffset

Allows to store not only a date, but have more precision
for the time component

Provides date and time related support to applications
deployed over the globe

“date” Data Type 1-3

Stores only the date without storing the time

Range is January 1, 0001 to December 31, 9999

By default, the date is displayed in YYYY-MM-DD format

Occupies 3 bytes, and has a precision of 10 digits
The image shows selecting the date data type in SQL Server 2008.

Syntax
DECLARE @local_variable [AS] data_type[ = value ]
Example
DECLARE @admissionDate date = '09-08-2009';
SELECT @admissionDate;
Output
2009-09-08
Displays the admission date of a student in a university

DECLARE @admissionDate date = GETDATE()
SELECT @admissionDate
Output
Example
2009-08-15
DECLARE @admissionDate date = '09-08-2009
10:30:25';
SELECT @admissionDate;
Output
Example
2009-09-08
Returns the current date
Stores only the date component

“time” Data Type 1-4

Stores only the time component

The time(7) data type from the Data Type dropdown seen in
Design view can be defined in a column

The precision is specified as time(n), where n represents the
precision value and should be in the range 0 to 7
The image shows selecting the time data type in SQL Server 2008.


Supports up to 100 nanoseconds of accuracy

Range is from 00:00:00.0000000 to 23:59:59.9999999 and
default precision is 7 digits

Truncates the remaining decimal values having precisions more
than 7 digits
The following table summarizes the result in the precision value, and its
corresponding storage size, based on the different integer values passed as
a parameter to the time data type.
Scale Result (precision,
scale)
Storage
(bytes)
time (16, 7) 5
time(0) (8, 0) 3
time(1) (10, 1) 3
time(2) (11, 2) 3
time(3) (12, 3) 4
time(4) (13, 4) 4
time(5) (14, 5) 5
time(6) (15, 6) 5
time(7) (16, 7) 5

Syntax
DECLARE @local_variable time [(fractional seconds
precision)] [ = value ]
where,
@local_variable: represents the name of a variable
fractional seconds precision: specifies the
number of digits ranging from 0 to 7 for the
fractional part of the seconds
value: represents the value assigned to the variable

The following example shows all the possible declarations using the time data type.
DECLARE @startTime time = '10:10:30.1234567';
DECLARE @startTime1 time(0) = '10:10:30.1234567';
Example
SELECT @startTime;
SELECT @startTime1;
SELECT @startTime2;
SELECT @startTime3;
SELECT @startTime4;
SELECT @startTime5;
SELECT @startTime6;
SELECT @startTime7;
Output
10:10:30.1234567
10:10:30
10:10:30.1
10:10:30.12
10:10:30.123
10:10:30.1235
10:10:30.12346
10:10:30.123457
10:10:30.1234567

“datetime2” Data Type 1-4

Is an enhancement to datetime

The datetime2(7) data type from the Data Type dropdown
seen in Design view can be defined in a column

Range is from January 1, 0001 to December 31, 9999

The default precision of datetime2 data type is 7 digits

Truncates the remaining decimal values having precision more
than 7 digits

Stores and displays date and time together in varying lengths
from 19 (YYYY-MM-DD hh:mm:ss) to 27 (YYYY-MM-DD
hh:mm:ss.0000000) characters in length
The image shows selecting the datetime2 data type in SQL
Server 2008.

a parameter to the datetime2 data type.
Scale Result
(precision, scale)
Storage
(bytes)
datetime2 (27, 7) 8
datetime2(0) (19, 0) 6
datetime2(1) (21, 1) 6
datetime2(2) (22, 2) 6
datetime2(3) (23, 3) 7
datetime2(4) (24, 4) 7
datetime2(5) (25, 5) 8
datetime2(6) (26, 6) 8
datetime2(7) (27, 7) 8

Syntax
DECLARE @local_variable datetime2
[(fractional seconds precision)] [ = value ]
where,
fractional seconds precision: specifies the number of
digits ranging from 0 to 7 for the fractional part of the seconds

The following example shows all the possible declarations in the datetime2 data
type.
DECLARE @bookingTime datetime2 = '2009-09-08 11:59:11.1234567';
DECLARE @bookingTime1 datetime2(0) = '2009-09-08 11:59:11.1234567';
DECLARE @bookingTime8 datetime2(7) = '2009-09-08
11:59:11.1234567';15.5
Example
SELECT @bookingTime;
SELECT @bookingTime1;
Output
2009-09-08 11:59:11.1234567
2009-09-08 11:59:11
2009-09-08 11:59:11.1
2009-09-08 11:59:11.12
2009-09-08 11:59:11.123
2009-09-08 11:59:11.1235
2009-09-08 11:59:11.12346
2009-09-08 11:59:11.123457
2009-09-08 11:59:11.1234567

“datetimeoffset” Data Type 1-4

Is an extension to the datetime2 data type

Allows you to store a date and time (based on 24-hour clock)
that is time zone aware

The time zone offset is indicated as + or - hh:mm, where hh
represents the hours and mm represents the minutes

The valid time zone range is from -14:00 through +14:00

The default precision of datetimeoffset data type is 7
digits, and the time portion has an accuracy upto 100
nanoseconds
The image shows selecting the datetimeoffset data type in SQL
Server 2008.

a parameter to the datetimeoffset data type.
Scale Result
(precision, scale)
Storage
(bytes)
datetimeoffset (34, 7) 10
datetimeoffset(0) (26, 0) 8

Syntax
DECLARE @local_variable datetimeoffset [(fractional
seconds precision)] [ = value ]
where,
fractional seconds precision: specifies the number
of digits ranging from 0 to 7 for the fractional part of the
seconds

The following example shows all the possible declarations in the datetimeoffset data
type.
DECLARE @sunriseTime datetimeoffset = '2009-09-08 06:59:11.1234567';
DECLARE @sunriseTime1 datetimeoffset(0) = '2009-09-08 06:59:11.1234567';
Example
SELECT @sunriseTime;
SELECT @sunriseTime1;
Output
2009-09-08 06:59:11.1234567 +00:00
2009-09-08 06:59:11 +00:00
2009-09-08 06:59:11.1 +00:00
2009-09-08 06:59:11.12 +00:00
2009-09-08 06:59:11.123 +00:00
2009-09-08 06:59:11.1235 +00:00
2009-09-08 06:59:11.12346 +00:00
2009-09-08 06:59:11.123457 +00:00
2009-09-08 06:59:11.1234567 +00:00

SPARSE Columns 1-2

An ordinary column that reduces the storage space occupied by a
column having null values

Use the SPARSE keyword to declare a column

Data types such as geography, geometry, image, ntext,
text, and timestamp cannot be marked as SPARSE

SPARSE columns can also be used with column sets and filtered
indexes

A column set is an additional column representing all the sparse
columns added to the table as an xml-typed column

Filtered indexes can be used to display only the rows that have
populated values in order to create a smaller and more efficient
index
Syntax
CREATE TABLE TABLENAME (ColumnName datatype SPARSE)
where,
SPARSE: indicates that it is a sparse column

SPARSE Columns 2-2
The following example creates a table named Customers with five columns.
Among the five columns, the columns, ContactNumber and Comments, are
set as sparse columns using the SPARSE keyword. By marking the columns as
sparse, no space will be allocated for null values stored in these columns.
CREATE TABLE Customers
(
FirstName varchar(25) NOT NULL,
LastName varchar(25) NOT NULL,
ContactNumber varchar(15) SPARSE NULL,
Salary money NOT NULL,
Comments varchar(1000) SPARSE NULL
)
Example
The following example shows the creation of a table with sparse columns and
a column set.
CREATE TABLE Customers
(
FirstName varchar(25) NOT NULL,
LastName varchar(25) NOT NULL,
ContactNumber varchar(15) SPARSE NULL,
Salary money NOT NULL,
Comments varchar(1000) SPARSE NULL,
AllSparseColumns xml COLUMN_SET FOR
ALL_SPARSE_COLUMNS
)

Wide Tables

In SQL Server, a table can have a maximum of 1024 columns

A wide table, a new special table type in SQL Server 2008,
enables you to increase the total number of columns to
30,000 by making use of sparse columns and column sets

The number of indexes and statistics is also increased to
1,000 and 30,000 respectively
 To convert a table into a wide table, you add a column set to
the table definition
 Wide tables has unique performance considerations, such as
increased run-time and compile-time memory requirements

Wide Tables - Disadvantages

Increased cost to maintain indexes on the table because
wide tables define up to 30,000 columns

When a column is added or removed from a wide table, the
SQL query for that particular column becomes invalid as it
needs to be rewritten

When data is added or removed from a wide table, the
performance gets affected

Spatial Data Types

Spatial data represents information about the geographical
location and the shape of objects, primarily on the earth

Spatial data provides information that can be used in
different scenarios such as:

Analyzing regional, national, or international sales
trends

Deciding where to place a new store based on
proximity to customers and competition

Navigating to a destination using a Global Positioning
System (GPS) device

Allowing customers to track the delivery of a parcel

Assessing the impact of environment changes such as
identifying houses at risk of floods

“geometry” and “geography” Data Types

geometry and geography are two spatial data types in
SQL Server 2008

These data types include properties and methods to perform
operations such as calculating distances between locations
 geometry data type is used to store data of a flat 2-D
surface having XY coordinates that represent points, lines,
and polygons in a two-dimensional space

The geography data type uses latitude and longitude
angles to find the points on the earth
The image shows selecting the geometry and geography data
types in SQL Server 2008.

Spatial Data Objects
Object Description
Point A zero-dimensional object that represents a single
location
MultiPoint A series of zero or more points that are grouped
together
LineString A one-dimensional object that represents sequence
of points that are connected by line segments to
make a complete line
MultiLineString A set of one or more LineString instances.
Polygon A two-dimensional shape representing a ring
MultiPolygon A set of one or more geometry or geography
Polygon instances
GeometryCollection A set of zero or more geometry instances
The geometry and geography data types have 11 spatial
data objects, also called as instance types.

Point
Example
-- Creating a Point geometry
DECLARE @spoint geometry;
SET @spoint = geometry::Parse('POINT(2 5)');
SELECT @spoint
In this example, a variable named @spoint is declared using
the geometry data type. Here, a point is plotted on the graph at
the coordinates (2, 5).
Output

MultiPoint
Example
-- Creating a MultiPoint geometry
DECLARE @mpoint geometry;
SET @mpoint = geometry::Parse('MULTIPOINT((6
8), (5 7))');
SELECT @mpoint
In this example, a variable named @mpoint is declared using the
geometry data type. Here, two points are plotted on the graph
at the coordinates (6,8) and (5,7).
Output

LineString
Example
-- Creating a LineString geometry
DECLARE @line geometry;
SET @line = geometry::Parse('LINESTRING(1 1, 4
5, 10 13, 19 25)');
SELECT @line
In this example, a variable named @line is declared using the
geometry data type. Here, a sequence of points is plotted on
the graph at the coordinates (1,1), (4,5), (10,13) and (19,25).
These sequence of points are connected by intermediate line
segments to make it a complete single line starting from (1,1)
till (19,25).
Output

MultiLineString
Example
-- Creating a MultiPolygon geometry
DECLARE @multipoly geometry
SET @multipoly =
geometry::Parse('MultiLineString ((0 0, 0 2, 2
3, 3 0, 0 0),
(1 1, 1 2, 2 1, 1 1))');
SELECT @multipoly
In this example, a variable named @multiline is declared using
the geometry data type. Here, two sets of sequence of points are
plotted on the graph. The first set has the coordinates (0,2), (1,1),
and the second set has the coordinates (1,2), (2,1), (2,2). Each set
of these sequence of points are connected to make a single line.
Output

Polygon
Example
-- Creating a Polygon geometry
DECLARE @poly geometry
SET @poly = geometry::Parse('POLYGON((0 2, 10
3, 3 4, 0 2))');
SELECT @poly
In this example, a variable named @poly is declared using the
geometry data type. Here, a sequence of points is plotted on the
graph with the coordinates (0,1), (1,5), (5,5), (5,1), and (0,1). Note
that the first and the last coordinate values are the same to make a
ring formation, in order to create a polygon.
Output

MultiPolygon
Example
-- Creating a MultiPolygon geometry
DECLARE @multipoly geometry
SET @multipoly = geometry::Parse('MultiPolygon
(((0 0, 0 2, 2 3, 3 0, 0 0),
(1 1, 1 2, 2 1, 1 1)))');
SELECT @multipoly
In this example, a variable named @multipoly is declared using
the geometry data type. Here, two set of sequence of points are
plotted on the graph to create two polygons. The output displayed
will show one polygon placed inside another polygon.
Output

GeometryCollection
Example
-- Creating a GeometryCollection geometry
DECLARE @geomcollection geometry;
SET @geomcollection =
geometry::Parse('GEOMETRYCOLLECTION(POINT(4
4), LINESTRING(3 3, 8 3), POLYGON((0 2, 13 3,
4 5, 0 2)))');
SELECT @geomcollection
In this example, a variable named @geomcollection is declared
using the geometry data type. Here, three different geometric
shapes, a point, a line, and a polygon are displayed simultaneously.
Output

Spatial Reference Identifiers (SRIDs)

Each spatial instance has an associated SRID

An SRID is a unique id used to determine a coordinate
system that enables to uniquely identify a specific position
on earth

SQL Server Database Engine uses SRID as 0 for geometry
data type, which is the default one

In geography data type, each position on earth is assigned
a specific SRID

The SRIDs can be viewed from a special table called
sys.spatial_reference_systems
The following code demonstrates how to retrieve data from the sys.spatial_reference_systems table. This table may
have six columns and more than 300 rows. Here, only first five rows and two columns are retrieved.
SELECT TOP 5 spatial_reference_id, unit_of_measure
FROM sys.spatial_reference_systems
Example
Output
spatial_reference_id
unit_of_measure
4120 metre
4121 metre
4122 metre
4123 metre
4124 metre

Static Methods 1-2
Method Description
STPointFromText Creates a Point instance
STMPointFromText Creates a MultiPoint instance
STLineFromText Creates a LineString instance
STMLineFromText Creates a MultiLineString instance
STGeomCollFromText Creates a GeometryCollection
instance
 You can insert new items of spatial data by using a static
method
 The most commonly used static method is
STGeomFromText()
 This method constructs a new instance from either a
geometry or geography data type
 The STGeomFromText() method has two parameters
 The first parameter represents the type of geometry or
geography instance that is to be created
 The second parameter represents the SRID of the instance
to be constructed

Static Methods 2-2
Syntax
geometry::STGeomFromText('geometry_tagged_text', SRID)
where,
geometry_tagged_text: represents the shape of
geometry/geography instance to be constructed
SRID: is an int expression representing the position on the earth
In this example, a variable named @shapepoly is declared using the geometry data type. Here, a polygon is created with
the coordinates (0,2), (10,3), (3,4) and (0,2) using the STGeomFromText() method.
DECLARE @shapepoly geometry
SET @shapepoly = geometry::STGeomFromText
('POLYGON((0 2, 10 3, 3 4, 0 2))',4326);
SELECT @shapepoly
Example
Output

CONVERT() Function 1-2
Conversion process in SQL Server 2005 Conversion process in SQL Server 2008

The CONVERT() function in SQL Server 2008 converts binary data into
character data.

CONVERT() Function 2-2
CONVERT( data_type [( length ) ] , expression[, style ])
Syntax
SELECT CONVERT(varbinary(6),'aptech')
SELECT CONVERT(varchar(18), 0x617074656368, 0) AS 'Style 0'
The following example demonstrates the CONVERT() function to convert
character data to binary, and thereafter the binary result back into character
data.
Example
While converting charactertobinary / binarytocharacter,
Style “0”: converts binary to varchar
Style “1”: converts binary to varchar but the values stay the same
Style “2”: strips the '0x' but leaves the rest of the values
where,
data_type: is the target data type (includes xml, bigint, and sql_variant)
length: An optional integer that specifies the length of the target data type
expression: is any valid expression
style: is an integer expression that specifies how the CONVERT() function
is to translate the expression. If style is NULL, NULL is returned

Enhancements in “DATEPART()” 1-2

Retrieves values of individual components that
make up the date and time data types
 Introduces arguments microsecond, nanosecond, and
TZoffset, ISO_WEEK
where,
datepart: is the argument name whose date or time value is to be
extracted from the date expression
date: is an expression that evaluates to a value of type date, time,
smalldatetime, datetime, datetime2, or datetimeoffset
DATEPART ( datepart, date)
Syntax

Enhancements in “DATEPART()” 2-2
SELECT DATEPART(YEAR, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(QUARTER, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(MONTH, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(DAYOFYEAR, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(DAY, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(WEEK, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(WEEKDAY, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(HOUR, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(MINUTE, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(SECOND, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(MILLISECOND, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(MICROSECOND, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(NANOSECOND, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(TZOFFSET, '2007-06-01 12:10:30.1234567');
SELECT DATEPART(ISO_WEEK, '2007-06-01 12:10:30.1234567');
Example Output
2007
26
152
1
22
6
12
10
30
123
123456
12345670
0
0
22

Enhancements in “DATENAME()” 1-2

The DATENAME() function retrieves and returns the date and
time values in the form of character strings

The DATENAME() function supports the microsecond,
nanosecond, TZoffset and ISO_WEEK arguments
where,
datepart: is the argument name whose date or time value is
to be extracted from the date expression
date: is an expression that can be resolved to a date, time,
smalldatetime, datetime, datetime2, or
datetimeoffset value.
DATENAME ( datepart, date)
Syntax

Enhancements in “DATENAME()” 2-2
SELECT DATENAME(YEAR, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(QUARTER, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(MONTH, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(DAYOFYEAR, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(DAY, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(WEEK, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(WEEKDAY, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(HOUR, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(MINUTE, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(SECOND, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(MILLISECOND, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(MICROSECOND, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(NANOSECOND, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(TZOFFSET, '2007-06-01 12:10:30.1234567');
SELECT DATENAME(ISO_WEEK, '2007-06-01 12:10:30.1234567');
Example Output
2007
2
June
152
1
22
Friday
12
10
30
123
123456
12345670
0
+00:00
22

Compound Assignment Operators 1-2

SQL Server 2008 supports five compound assignment
operations:

Addition (+=)

Subtraction (=)

Multiplication (*=)

Division (/=)

Modulus (%=)

The use of compound assignment operators result in faster
coding and compact code

Can be used in the SET clause of either the UPDATE or
SET statements or wherever assignment is normally
allowed
where,
operand1: is a userdefined variable
operand2: is a userdefined variable or a constant value
SET operand1 += operand2;
SET operand1 -= operand2;
SET operand1 *= operand2;
SET operand1 /= operand2;
SET operand1 %= operand2;
Syntax

Compound Assignment Operators 2-2
DECLARE @value AS MONEY = 10.00;
SET @value += 2.00;
SELECT @value;
SET @value -= 2.00;
SELECT @value;
SET @value *= 2.00;
SELECT @value;
SET @value /= 2.00;
SELECT @value;
SET @value %= 2.00;
SELECT @value;
Example Output
12.00
10.00
20.00
10.00
0.00

Summary

SQL Server 2008 has many enhancements in Transact
SQL statements including the new date and time data
types, sparse columns, wide tables, spatial data types,
and so on.

SQL Server 2008 has enhanced functions such as the
CONVERT() function, the DATE functions, and the
XQuery functions.

SQL Server 2008 has also introduced the compound
assignment operators such as +=, =, and so forth.

Sql server ___________session 2(sql 2008)

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