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IT390 Business Database Administration
Unit 5 :
Backup and Restoring Tasks
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 1
Objectives
•
•
•
•
•
•
Backup, Recover and Replicate a Microsoft SQL Database
Server.
Implement database backup in SQL Server 2000.
Explain the importance of database restoration in SQL Server
2000.
Explain various database recovery models in SQL Server 2000.
Restore and rebuild a master database.
Explain the process and features of Replication.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 2
SQL Server Backup
• SQL Server supports several types of backup:
 A complete backup makes a copy of the entire
database
 A differential backup makes a copy of the database
changes since the last complete backup
 Differential backups are faster and can be taken more
frequently
 Complete backups are simpler to use for recovery
• The transaction log also needs to be periodically backed
up
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 3
Database Recovery
• Both data and log files are created by SQL Server
• SQL Server provides a wizard for setting up database
maintenance plan, e.g., scheduling database and log
backups
• To recover a database with SQL Server:
 The database is restored from a prior database
backup
 Log after images are applied to the restored database
 At the end of the log, changes from any transaction
that failed to commit are then rolled back
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 4
SQL Server Recovery Models
• Three recovery models

Simple recovery: neither logging is done nor log
records applied:
• To recover a database is to restore the database to the
last backup
• This method can be used for a database that is never
changed


Full recovery: all database changes are logged
Bulk-logged: all changes are logged except
those that cause large log entries
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 5
Activity
Julia, the DBA at Ralphsoft Inc., is assigned the responsibility
of making backups of critical databases every Friday.
How can she perform this task?
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 6
Backups
•
A backup of a database is another copy of the database
stored in another physical location, which may be a disk or
a tape.
•
In SQL Server 2000, you can make the following backups:




Full backup
Differential backup
Transaction Log backup
File Group backup
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 7
Class Activity
•
List the tasks that need to done before performing a
backup on a critical database.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 8
Performing Backups
•
In SQL Server 2000, you can perform backups using:

Enterprise Manager

T-SQL

Backup Wizard
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 9
Class Activity
•
List the steps to perform backup using Enterprise
Manager (Pages 7.7 – 7.19).
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 10
Performing Backup Using T-SQL
•
You can perform a backup using T-SQL in the following manner:

EXEC sp_addumpdevice 'disk',
'master_backup',
'c:\Program Files\Microsoft SQL
Server\MSSQL\BACKUP\ masterbackup.bak'
BACKUP DATABASE master TO master_backup
WITH INIT
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 11
Class Activity
•
What is the output of the following T-SQL statement?

EXEC sp_addumpdevice 'disk',
'Inventorylog',
‘C:\BACKUPS\inventory_backup.dat‘
BACKUP LOG inventory TO
Inventorylog
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 12
Class Activity
(cont)
•
Write the command to create a backup for the Employee
database named Employee_backup.
•
The backup must be stored on a disk device named
empbackup at the location, C:\Backups\empbackup.bak.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 13
Class Activity (cont)
•
List the steps to perform a backup using the Backup wizard.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 14
Recovery
•
Recovery is a method provided by SQL Server 2000 to
restore the database that you backed up.
•
You can recover your data from any of the following types
of failures:

Permanent loss of servers

Media failures

User errors
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 15
Recovery (cont)
•
The following recovery models are available in SQL
Server 2000:



Simple recovery
Full recovery
Bulk-logged
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 16
Restoration
•
SQL Server provides the following options to restore a
database:



Restore the database and its transaction log.
Restore from a full database backup to a differential
backup.
Restore from a file group backup.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 17
Class Activity
•
What is achieved by the following T-SQL statement?

RESTORE DATABASE SALES FROM
SALES_BACKUPRESTORE LOG saleslog
FROM saleslog_backup WITH RECOVERY
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 18
Restoring and Rebuilding the Master Database
•
•
•
The master database stores various types of configuration
information about SQL Server and all the user-defined
databases.
SQL Server provides a utility called rebuildm to rebuild the
master database.
You cannot rebuild the master database if you do not have
its backup.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 19
Activity
•
List the steps to rebuild and restore the master database in case of
a failure.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 20
Distributed DBMS Architecture
• In a distributed DBMS environment, multiple
copies of a database are maintained across
geographical regions. Data is generally stored in
a region or department where it is needed the
most.
Location A
Location B
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 21
Location C
Database Replication
• Database replication is the process of making the
copies of a database available to different
database users spanning across different
locations. Data is replicated for:
 Data sharing
 Reduction in network traffic
 Database backup
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 22
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 23
Database Replication (cont.)
• Different database replication models are used for
making replicas of the main database. These
models are:
 Snapshot
 Transactional
 Merge
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 24
Snapshot Database Replication Model
• In the snapshot database replication model, the replica
of the main database consists of an exact copy of the
data and database objects present in the central
database at any point in time.
Main
Database
XXXX
YYYY
XXYY
Location A
Local
Database
Location B
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 25
XXXX
YYYY
XXYY
Local
Database
XXXX
YYYY
XXYY
Location C
Snapshot
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 26
Transactional Database Replication Model
• The transactional replication model is used in
organizations where data needs to be replicated as
soon as transactions take place or as data gets
modified in the central database.
Main
Database
Location
XXXX
YYYY
XXYY XXX
YYYY
A
XXYY
XXX
XXX
Local
Database
XXX
YYYY
XXYY
Location B
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 27
Local
Database
XXXX
YYYY
XXYY
Location C
Transactional……….Changes only
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 28
Merge Database Replication Model
• The merge database replication model is used by
organizations in which local users can modify the local
database copies without simultaneously updating the
central database.
Main
Database
Main
Database
XXX
YYY
XXY
XXXX
YYYY
XXYY
XXX
YYY
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 29
XXY
XXX
YYY
XXY
XXX
YYY
XXY
XXX
YYY
XXY
Continuous Merges may be inefficient
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 30
Summary
• Creating a Backup and Managing a restore with Transact SQL
and Enterprise Manager is a key skill
• Database restoration is a key procedure in case of failure. A
business cannot afford to lose their data
• There are several options for backing up and recovering
databases.
• Replication is the maintenance of data at multiple sites. There
are several methods to replicate data.
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 31
Summary
 Did
you understand the key points from
the Lesson?
 Do
you have any questions?
©2006 ITT Educational Services Inc.
Course Name: IT390 Business Database
Administration Unit 5 Slide 32