1. Week 9 – Chapter 8 SQL 710 Methods to Backup Databases
Types of data to be backed up
Recovery models
Recovery methods
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2. Methods to Back up Data SQL 710
Maintenance Wizard (Chapter 7) to create maintenance plan with scheduled backups
Enterprise Manager to schedule job to perform backup or to perform unscheduled backup as required
T-SQL commands
Specialized packages such as Backup Exec or Arcserv (not discussed here)
SQL 710

3. Prevent Loss of Data SQL 710 Have a strategy:
To minimize data loss (malicious use of delete, update statement, viruses, natural disaster, theft)
To recover lost data
To restore data with minimal cost and impact
Backup regularly:
Backup frequently if your database is OLTP
Backup less frequently if your database is OLAP
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4. Database Recovery Models
Set Database Recovery Model:
Full Recovery Model
Bulk logged recovery model
Simple Recovery Model
Modify a database recovery model
Alter database pubs
Set recovery to bulk_logged
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5. Backups
SQL Server allows backups to occur while users continue to work with the database
Backs up original files and records their locations
Captures in the backup all database activities that occur during the backup process
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6. Backups (ctd) SQL 710 Who can perform backup?
Members of the sysadmin fixed server role
Members of the db_owner and db_backupoperators fixed database roles
Where to store backup?
Hard disk file
Tape
A location identified by a Named Pipe (3rd party software package)
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7. When to backup System Databases
After modifying the master database:
Using CREATE DATABASE, ALTER DATABASE or DROP statement
Executing certain Stored Procedures
After modifying the msdb database
After modifying the model database
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8. When to backup User Databases
After creating a database
After creating an index
After creating a transaction
After performing un-logged operations:
BACKUP WITH TRUNCATE_ONLY OR NO_LOG OPERATIONS
SELECT INTO statement
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9. Restricted Activities during backup
Creating or modifying database
Performing autogrow operations
Creating indexes
Performing non-logged options
Shrinking a database
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10. Create a Backup device SQL 710
A backup file that is created before it is used for a backup is called a backup device
Why create permanent backup devices?
To reuse backup files for future backups
To automate the backup
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11. Create a Backup device(ctd)
Use sp_addumpdevice system procedure:
Specify a logical name
Logical and physical Names are stored in the sysdevices system table
Example:
Use master
Exec sp_addumpdevice ‘disk’ , ‘mybackupfile’, ‘c:\Backup|mybackupfile.bak’
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12. Perform Backup without backup device
Why create backup without backup device?
To perform one time backup
To test backup operation that you plan to automate
How to use backup database statement:
Specify the media type (disk, tape, or Named Pipe)
Specify the complete path and full Name
Example:
Use master
Backup database Northwind
To Disk = ‘c:\temp\mycustomers.bak’
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13. Types of Backup Methods
Full database backup
Differential backup
Transaction log backup
File or File group backup
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14. Full Database Backup SQL 710 Provides a baseline
Backs up original files, objects and data
Backs up portions of the transaction log
Example:
Use master
Exec sp_addumpdevice ‘disk’, ‘NwindBac’ ,
‘D:\mybackupdir\Nwindbac.bak’
Backup database Northwind to NwindBac
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15. Full Database Backup Options
WITH INIT: overwrites any previous backup on that file
WITH NOINIT : appends the full database backup to the backup file. Any previous backup left intact.
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16. Differential database backup
Use on frequently modified databases
Requires a full database backup before
Backs up database changes since the last full database backup
Saves time in both backup and restore processes
Example:
Backup Database Northwind
Disk = ‘D:\Mydata|Mydiffbackup.bak’
WITH DIFFERNTIAL
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17. SQL 710 Transaction log backup Requires a Full database backup
Backs up all database changes from the last BACKUP LOG statement to the end of the current Transaction log.
Truncates the transaction log
Example:
Use master
Exec sp_addumpdevice ‘disk’, ‘Nwindbaclog’,
‘D:\Baclup\Nwind backuplog.bak’
Backup log Northwind To NwindBaclog
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18. Backup using No-truncate Option
Saves the entire Transaction log even if the database is inaccessible
Doesn’t purge the Transaction log of committed Transactions
Allows data to be recovered up to time of system failure
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19. Clear the Transaction log
Use Backup statement to clear transaction log
Use truncate only or no_log option
Can’t recover changes
Is not recorded changes
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20. Database file or filegroup backup
Use on very large databases
Backup the database files individually
Ensure that all database files in File group are backed up
Back up transaction log
Example:
Backup database phoneorders
File = Orders2 To orderbackup2
Backup log phoneOrders to orderlog
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