Microsoft SQL Server 2008 R2 Unleashed- P9 docx

Following is an overview of the new features provided in SQL Server 2008: columns and column sets, row-level and page-level data compression types; Hierarchyid data type; spatial data ty

Running SQL Server 2008 inside a virtual operating environment requires at least one

license per virtual operating environment Within each virtual operating environment, the

license allows you to run one or more instances of SQL Server 2008 The license for a

virtual operating environment can be a server/CAL license or a processor-based license If

using a processor-based license, you must purchase a processor license for each processor

that the virtual machine accesses The total number of physical and virtual processors

used by the virtual operating system environments cannot exceed the number of software

licenses assigned to that server However, if you are running Enterprise Edition and all

physical processors in the machine have been licensed, you may run an unlimited number

of virtual operating environments on that same machine

Multiple Instances of SQL Server

An option to virtualization is multi-instancing With multi-instancing, multiple copies of

SQL Server can be run concurrently in a single instance of an OS Multi-instancing for SQL

Server 2008 can take place both in a virtual environment or in a physical environment

Although multi-instancing offers a relatively high degree of isolation between copies of

SQL Server 2008, this isolation takes place at the application level (instead of at the OS

level)

In SQL Server 2008, the Workgroup and Standard Editions now allow you to run any

number of instances of the server software in one physical or virtual operating system

envi-ronment on the licensed server Previously, only the Enterprise Edition of the server license

allowed multi-instancing

Summary

This chapter examined the various platforms that support SQL Server 2008 R2 and

reviewed and compared the various editions of SQL Server 2008 that are available Which

platform and edition are appropriate to your needs depends on scalability, availability,

performance, licensing costs, and limitations The information provided in this chapter

should help you make the appropriate choice

Chapter 2, “What’s New in SQL Server 2008,” takes at closer look at the new features and

capabilities provided with the various SQL Server 2008 editions

CHAPTER 1 SQL Server 2008 Overview

What’s New in SQL

Server 2008

New SQL Server 2008 Features SQL Server 2008

Enhancements

SQL Server 2005 provided a number of significant new

features and enhancements over what was available in SQL

Server 2000 This is not too surprising considering there was

a five-year gap between these major releases Microsoft SQL

Server 2008 is not as much of a quantum leap forward from

SQL Server 2005, but it provides a number of new features

and enhancements to further extend the performance,

relia-bility, availarelia-bility, programmarelia-bility, and ease of use of SQL

Server This chapter explores the new features provided in

SQL Server 2008 and SQL Server 2008 R2, as well as many

of the enhancements to previously available features

New SQL Server 2008 Features

So what does SQL Server 2008 have to offer over SQL Server

2005? Following is an overview of the new features

provided in SQL Server 2008:

columns and column sets, row-level and page-level

data compression

types; Hierarchyid data type; spatial data types;

user-defined table type

operators, GROUPING SETS, MERGE statement, row

constructors, table-valued parameters, INSERT over

DML, new date and time functions

statistics, FORCESEEK query hint, hash values for

CHAPTER 2 What’s New in SQL Server 2008

finding similar queries in the plan cache, Plan Guide Successful and Plan Guide

Unsuccessful event classes, Guided/Misguided Plan Executions/sec Performance

Monitor counters, LOCK ESCALATION option for ALTER TABLE, hot-add CPUs

SQL Server Audit

Capture, Change Tracking, the Data Collector, Policy-Based Management, SQL Server

Extended Events, Resource Governor

error list window, multiserver queries, PowerShell integration

SQL Server 2008 R2 further enhances SQL Server 2008 with the following new features:

Two new premium editions to meet the needs of large-scale datacenters and data

warehouses:

SQL Server 2008 R2 Datacenter

SQL Server 2008 R2 Parallel Data Warehouse

SQL Server Utility for Multi-Server Management

PowerPivot for Excel and SharePoint

A number of new Reporting Services features including Report Builder 3.0, report

parts, shared datasets, Sparklines and data bars, indicators, calculating aggregates of

aggregates, maps, lookup functions

The following sections take a closer look at each of these new features and, where

appro-priate, provide references to subsequent chapters where you can find more information

and detail about the new features

New Storage Features

SQL Server 2008 provides a set of new features to reduce storage requirements and

improve performance

One of the new features is FILESTREAM storage FILESTREAM storage is a property that can

be applied to varchar(max) columns; it enables SQL Server applications to store

unstruc-tured data, such as documents and images, directly in the NTFS file system while still

maintaining the behavior of a database column The advantages of FILESTREAM storage

are improved performance and increased size of BLOB data, expanding from the 2GB limit

of image columns to the available space in the file system For more information on using

FILESTREAM storage, see Chapter 42, “What’s New for Transact-SQL in SQL Server 2008.”

Other storage features introduced in SQL Server 2008 are sparse columns and column sets

Sparse columns are ordinary columns that have an optimized storage format for null values

If you use sparse columns, you can also define a column set on the table that will return

all sparse columns in the table A column set is an untyped XML representation that

combines all the sparse columns of a table into a structured output For more information

on defining sparse columns and column sets, see Chapter 24, “Creating and Managing

Tables.”

Row-level and page-level data compression also are introduced in SQL Server 2008 Data

compression helps to reduce both storage and memory requirements as the data is

compressed both on disk and when brought into the SQL Server data cache Row-level

compression isn’t true data compression but implements a more efficient storage format

for fixed-length data Page-level compression is true data compression, using both column

prefix and dictionary-based compression For more information on implementing data

compression, see Chapter 24

New Data Types

SQL Server 2008 introduces a handful of new data types Two of the most welcome of

these are the new DATE and TIME data types These new data types allow you to store

date-only and time-date-only values In addition, SQL Server now supports the DATETIME2 and

DATETIMEOFFSET data types DATETIME2 is a variation of the DATETIME data type that

supports datetime values from 0001-01-01 to 9999-12-31 23:59:59.999999

DATETIMEOFFSET supports UTC-based datetime values that are time zone aware

The new Hierarchyid data type is a common language runtime (CLR) user-defined type

(UDT) that provides a mechanism for representing and storing a tree structure in a table in

an efficient manner This data type is useful for storing data that represents a parent child,

tree-like structure such as an organizational structure or a graph of links between web

pages

Spatial data types are introduced in SQL Server 2008 as well There are two new spatial

data types: geometry and geography The geometry data type supports planar, or Euclidean

(flat-earth), data The geography data type stores ellipsoidal (round-earth) data, such as

GPS latitude and longitude coordinates These new data types support the storage and

manipulation of spatial data objects such as linestrings, points, and polygons

SQL Server 2008 also introduces a new user-defined table type that can be used as

parame-ters in stored procedures and functions, as well as for defining table variables in a batch or

the body of a stored procedure or function

For more information and examples on using the new SQL Server 2008 data types, see

Chapter 42

New Transact-SQL Constructs

What would a new SQL Server release be without new T-SQL commands and constructs to

further expand the power and capabilities of the T-SQL language? SQL Server 2008 is no

exception (although SQL Server 2008 R2 is an exception because no new T-SQL constructs

are introduced in R2) The new constructs provided in SQL Server 2008 include

performing an operation and assigning a value to a local variable (for example,

+=, *=)

CHAPTER 2 What’s New in SQL Server 2008

grouping operations in a single query

operations on a target table based on the results of a join with a source table

inserts within a single INSERT statement Also provides the ability to use the VALUES

clause to create a pseudo table of values in a subquery or common table expression

user-defined table types Table-valued parameters enable you to pass a table variable

con-taining multiple rows of data to a stored procedure or function without the need to

create a temporary table

To coincide with the new DATE and TIME data types, SQL Server 2008 also introduces a

few new date and time functions:

DATETIMEOFFSET(7) value

representing the current UTC time

value from the stored time zone offset to the specified time zone

for the specified time zone to a DATETIMEOFFSET UTC value

For more information and examples on using the new SQL Server 2008 T-SQL constructs,

see Chapter 42

New Performance Features

SQL Server 2008 also introduces some new features and enhancements for monitoring,

managing, and improving query performance Among these new features are filtered

indexes and statistics A filtered index is a nonclustered index defined on a subset of data

using a filter predicate to index only a portion of rows in the table Filtered statistics are

statistics defined on a subset of data in the table using a filter predicate A well-designed

filtered index can improve query performance, reduce index maintenance costs, and

reduce index storage costs compared with full-table indexes, especially when columns

contain a large number of rows with null or a single value that isn’t searched on but can

skew the index and statistics For more information on creating and using filtered indexes

and statistics, see Chapter 34, “Data Structures, Indexes, and Performance.”

SQL Server 2008 provides FORCESEEK as a new table and query hint for controlling how

SQL Server optimizes a query; it forces the optimizer to use only an index seek operation

to access the data in the referenced table or view For more information on using the

FORCESEEK hint, see Chapter 35, “Understanding Query Optimization.”

Plan guides were a feature introduced in SQL Server 2005 Plan guides can be used to

opti-mize the performance of queries when you cannot or do not want to change the text of

the query directly (for example, when queries in a third-party database application are not

performing as expected) SQL Server 2008 provides additional features related to plan

guides to make implementing and managing them easier Among these features are new

event classes (Plan Guide Successful and Plan Guide Unsuccessful) that can be monitored

via SQL Server Profiler to determine when plan guides are being applied There are also

two new Performance Monitor counters (Guided/Misguided Plan Executions/sec) that you

can use to monitor via Performance Monitor how often plan guides are being used or not

being used

SQL Server 2008 also now generates hash values for query plans in the plan cache The

sys.dm_exec_query_stats and sys.dm_exec_requests dynamic management views

(DMVs) now provide query hash and query plan hash values that you can use to help find

similar queries in the plan cache Locating similar queries can help you determine the

aggregate resource usage for similar queries and similar query execution plans so that you

can better focus your query tuning efforts and help identify which queries may get the

most benefit from using plan guides For more information on query plans and using plan

guides, see Chapter 35

To provide greater control of locking, SQL Server 2008 offers the new LOCK ESCALATION

table option This option specifies the allowed methods of lock escalation for a table The

default is AUTO, which allows the Database Engine to select the appropriate lock escalation

level for the query if a table is partitioned You can also specify TABLE to force full

table-level locking whether or not a table is partitioned A third option, DISABLE, prevents

esca-lation to a table-level lock in most cases For more details on locking and the LOCK

ESCALATION option, see Chapter 37, “Locking and Performance.”

One additional new feature in SQL Server 2008 Enterprise Edition is hot-add CPU Hot-add

CPU is the capability to dynamically add CPUs to a running system Additional CPUs can

be made available logically by online hardware partitioning, virtually through a

virtualiza-tion layer, or even physically by adding new hardware on systems that support adding

physical CPUs while the system is online Hot-add CPU, which requires hardware support,

is available only when you’re running Windows Server 2008 Datacenter or Enterprise

Edition

New Security Features

SQL Server 2005 provided the capability to encrypt data at the column level However,

this encryption was not transparent to the end users or applications Encrypting and

decrypting the data required coding changes to use the built-in encryption and decryption

functions SQL Server 2008 introduces transparent data encryption (TDE), which allows

for encrypting the entire database without affecting client applications The purpose of

TDE is to protect sensitive data in the event a database file or backup is stolen Encryption

is done in real-time at the page level as the data is written to disk and decrypted as the

data is read from disk The encryption is based on a database encryption key (DEK), which

is a symmetric key secured by using a certificate stored in the master database of the

server or an asymmetric key protected by an Extensible Key Management (EKM) module

CHAPTER 2 What’s New in SQL Server 2008

Extensible Key Management, which is also new with SQL Server 2008, enables you to store

the keys used to encrypt data separately from the data it protects SQL Server 2008 EKM

enables the encryption keys that protect the database files to be stored in a removable

device such as a smartcard, USB device, or a software-based Extensible Key Management

(EKM)/Hardware Security Module (HSM) module EKM facilitates separation of duties by

taking key management out of the hands of the database administrators

For more information on implementing and using transparent data encryption and

exten-sible key management, see Chapter 12, “Data Encryption.”

SQL Server already provides a number of existing audit methods (SQL Trace, C2 audit

mode, DDL triggers) In addition to these, SQL Server 2008 adds an additional audit

method: SQL Server Audit SQL Server Audit, based on the new Extended Events feature,

allows you to monitor server- or database-level events or groups of events You can set up

and monitor audit events at the server or database level and audit the audit actions

them-selves For more information on SQL Server Audit, see Chapter 13, “Security and

Compliance.”

New Database Administration Features

SQL Server 2008 introduced backup compression for Enterprise Edition With SQL Server

2008 R2, backup compression is supported in Standard and all higher editions (every

edition of SQL Server 2008 and later can restore a compressed backup, however) In

addi-tion to the space savings provided by compressed backups, compressing a backup also

typically increases backup speed because it requires less device I/O However, the I/O cost

savings comes at the expense of increased CPU usage caused by the compression process

For more information on compressing backups, see Chapter 14, “Database Backup and

Restore.”

Policy-Based Management is a new mechanism in SQL Server 2008 for managing one or

more instances of SQL Server 2008 SQL Server Policy-Based Management can help to

simplify management operations such as setting database options across multiple servers,

checking SQL Server configurations, or enforcing naming conventions, helping to reduce

the total cost of ownership (TCO) of administering multiple SQL Server instances SQL

Server Management Studio (SSMS) can be used to define and implement policies for

managing SQL Server instances, databases, or other SQL Server objects as well as

on-demand checking and enforcement of policies Checking and enforcement of these

poli-cies can also be scheduled using SQL Server Agent For more information on Policy-Based

Management in SQL Server, see Chapter 22, “Administering Policy Based Management.”

Currently, several options are available for troubleshooting or getting information about

SQL Server–generated events: SQL Server Profiler, SQL Server Log, dynamic management

views and functions, SQL Trace, trace flags, Windows Application and System logs,

perfor-mance counters, and so on SQL Server 2008 introduces a new event infrastructure,

Extended Events Extended Events is a general-purpose event-handling system for server

systems Currently, the Extended Events infrastructure supports the correlation of data

from SQL Server and, under certain conditions, the correlation of data from the operating

system and database applications Extended Events has the potential to make other

bleshooting options obsolete in future releases and become the common denominator for

troubleshooting purposes As mentioned previously, the new SQL Server Audit feature is

based on Extended Events For more information on configuring and using Extended

Events for monitoring SQL Server 2008, see Chapter 39, “Monitoring SQL Server

Performance.”

Resource Governor, another new technology in SQL Server 2008, enables you to manage

and control the allocation of resources for SQL Server according to workload Similarly

sized queries or requests that can, and should be, treated the same are assigned to a

work-load group as the requests are received Each workwork-load group is associated to a pool of

resources that represents the physical resources for SQL Server (currently, for SQL Server

2008, these resources are CPU and memory) Limits are specified on resource consumption

for these incoming requests In an environment where multiple distinct workloads are

present on the same server, Resource Governor enables you to differentiate these

work-loads and allocate shared resources as they are requested, based on the limits you specify

For more information on implementing and configuring Resource Governor, see Chapter

40, “Managing Workloads with the Resource Governor.”

Change Data Capture (CDC) and Change Tracking are new features in SQL Server 2008

with similar names but different purposes CDC is an asynchronous mechanism that

captures all changes of a data row from the transaction log and stores them in change

tables The information captured is available in relational format and can be accessed by

client applications such as extract, transform, and load (ETL) processes All intermediate

values of a row are stored Using Change Data Capture, you can avoid using expensive

techniques such as triggers, time stamp columns, and join queries to identify and capture

the changes made to data

Change Tracking, on the other hand, is a lightweight synchronous mechanism that tracks

data modifications but records only the fact that a row has changed Applications can use

Change Tracking to identify which rows have changed for a user table and refresh their

data stores with the latest values from these rows by requerying the table

For more information on using CDC and Change Tracking, see Chapter 42

New SQL Server Management Studio Features

SQL Server Management Studio (SSMS) was first introduced in SQL Server 2005 SSMS is a

full-featured, robust SQL Server administration and development tool However, there was

clearly room for improvement, and SQL Server 2008 provides some long-awaited

enhance-ments

One of the most anticipated (and missed) features in SSMS was a built-in T-SQL debugger

Prior to SQL Server 2005, SQL Server Enterprise Manager had a built-in T-SQL Debugger A

lot of users were disappointed a T-SQL debugger was not included with this version of

SSMS To debug T-SQL, you needed to install Visual Studio (VS) Fortunately, a built-in

debugger returns to SSMS in SQL Server 2008

Another long-awaited feature for SSMS is IntelliSense IntelliSense is a useful feature in the

Query Editor for looking up language elements and object names without having to leave

CHAPTER 2 What’s New in SQL Server 2008

the editor IntelliSense can even automatically complete and insert language elements

directly into your code

In conjunction with IntelliSense, SSMS also provides the error list window The error list

window displays all errors and warnings produced by IntelliSense as you develop your code

in the Database Engine Query Editor You can double-click the error message entry to

jump to the error location As you fix errors, they are automatically removed from the

error list window

One other new capability built in to SSMS in SQL Server 2008 is multiserver queries This

feature allows you to execute T-SQL statements against multiple servers defined in a server

group at the same time If you open a Query Editor from the server group in the

Registered Servers window, the T-SQL statements in the current Query Editor are executed

against all the servers in the group The results from the query can be merged into a single

results pane or can be returned in separate results panes for each server

For more details on these new features in SSMS, see Chapter 4, “SQL Server Management

Studio.”

PowerShell Integration

SQL Server 2008 provides integrated support for Windows PowerShell, a powerful scripting

shell that enables administrators and developers to automate server administration and

application deployment The Windows PowerShell language supports more complex logic

than Transact-SQL scripts, enabling SQL Server administrators to build more robust and

complex administration scripts

SQL Server provides two snap-ins to Windows PowerShell for creating scripts to manage

SQL Server:

A SQL Server provider, which enables a simple navigation mechanism similar to file

system paths where the drive is associated with a SQL Server management object

model and the nodes are based on the object model classes This allows you to use

familiar commands such as cd and dir to navigate the paths similar to the way you

navigate folders in a command prompt window

A set of cmdlets, which are commands used in Windows PowerShell scripts to

speci-fy a SQL Server action, such as running a SQLCMD script containing Transact-SQL or

XQuery statements

For more information on managing SQL Server using PowerShell, see Chapter 17,

“Administering SQL Server 2008 with PowerShell.”

New Premium SQL Server Editions

SQL Server 2008 R2 introduces two new premium-level editions of SQL Server: Datacenter

Edition and Parallel Data Warehouse

Built on SQL Server 2008 R2 Enterprise, SQL Server 2008 R2 Datacenter is designed to

deliver a high-performing data platform that provides the highest levels of scalability for

large application workloads, virtualization and consolidation, and management for an

organization’s database infrastructure Datacenter helps enable organizations to

cost-effec-tively scale their mission-critical environment Key features of Datacenter include

Application and multiserver management for enrolling, gaining insights, and

managing more than 25 instances

Highest virtualization support for maximum return on investment (ROI) on

consoli-dation and virtualization

High-scale complex event processing with SQL Server StreamInsight

Support for more than 8 processors and up to 256 logical processors

SQL Server 2008 R2 Parallel Data Warehouse is a highly scalable data warehouse

appliance-based solution Parallel Data Warehouse delivers performance at low cost through a

massively parallel processing (MPP) architecture and compatibility with hardware partners,

allowing you to scale your data warehouse to tens and even hundreds of terabytes Key

features provided by Parallel Data Warehouse include

Advanced data warehousing capabilities such as Star Join Queries and Change Data

Capture

Integration with SSIS, SSRS, and SSAS

Support for industry-standard data warehousing hub-and-spoke architecture and

par-allel database copy

SQL Server Utility for Multiserver Management

SQL Server 2008 R2 features new SSMS dashboards for observing information on more

than one server from the same screen by utilizing the new SQL Server Utility The SQL

Server Utility models an organization’s SQL Server–related entities in a unified view Utility

Explorer and SQL Server Utility viewpoints in SQL Server Management Studio provide

administrators a holistic view of SQL Server resource health Entities that can be viewed in

the SQL Server Utility include

Instances of SQL Server

Data-tier applications

Database files

Volumes

SQL Server Utility is covered in more detail in Chapters 4 and 39

PowerPivot for Excel and SharePoint

PowerPivot is a new tool that integrates SQL Server with Microsoft Excel and SharePoint to

create a self-service business intelligence (BI) solution for the enterprise PowerPivot for

Excel and SharePoint are client and server components that integrate Analysis Services

with Excel and SharePoint PowerPivot for Excel is an add-in that allows you to create

PowerPivot workbooks that can assemble and relate large amounts of data from different