Be Proactive: A Good DBA Goes Looking for Signs of Trouble

1. © 2019 IDERA, Inc. All rights reserved.
© 2021 IDERA, Inc. All rights reserved.
BE PROACTIVE:
GOOD DBA GOES LOOKING
FOR SIGNS OF TROUBLE
Database administrators (DBAs) are busier than ever these days, so
fighting fires is last thing they want to spend their time doing. A proactive
approach to database performance and maintenance helps keep DBAs
ahead of trouble and prevent little problems from turning into full-blown
emergencies.

2. © 2021 IDERA, Inc. All rights reserved.
ROUTINE DATABASE MAINTENANCE
• Most DBAs take full backups at regular intervals
• DBAs also need to consider implications of backups concerning recovery
• Backup frequency determines potential data loss from recovery

3. © 2021 IDERA, Inc. All rights reserved.
ROUTINE DATABASE MAINTENANCE
• Most DBAs take full backups at regular intervals
• DBAs also need to consider implications of backups concerning recovery
• Backup frequency determines potential data loss from recovery
BACKUPS
| RPO
• Recovery point object (RPO): Maximum amount of data organization is
willing to lose after recovery
• RPO dictates backup schedule rather than other way around
• Cost of achieving zero data loss is usually prohibitively high
| Backup all Databases
• Backup system databases as well as user databases
• Without system database backups, new user databases will not have any agent
jobs, logins, and permissions
| Verification
• Use CHECKSUM option during backup to perform corruption checks
• Use RESTORE VERIFYONLY to ensure that backups are complete and readable
without restoring database

4. © 2021 IDERA, Inc. All rights reserved.
ROUTINE DATABASE MAINTENANCE
• Most DBAs take full backups at regular intervals
• DBAs also need to consider implications of backups concerning recovery
• Backup frequency determines potential data loss from recovery
BACKUPS
| Backup Types
• Full backup: Contains all data in database
• Differential backup: Contains only data that has changed since last full backup
- Recovery: Need to restore most recent full backup before recovery point,
followed by most recent differential backup.
• Log backup: Latest full backup plus all transactions that occurred since previous
log backup.
- Recovery: Restore log backups in chronological order to reach recovery point
• Full copy only backup: Independent of regular backup sequence since it does
not modify log sequence number (LSN)

5. © 2021 IDERA, Inc. All rights reserved.
RECOVERY
• Be prepared for database failures
• Restore backups regularly
• Determine time needed to retrieve backup files and restore backups
including log files
• Test restore scripts beforehand so they are ready for use

6. © 2021 IDERA, Inc. All rights reserved.
INTEGRITY CHECKS
• Some database servers like SQL Server allow backing up corrupt
databases but it will not restore that backup
• Try to run DBCC CHECKDB before every backup for full corruption check on
entire database
• However, CHECKDB is resource intensive
• Frequency of integrity checks depends on amount of data
organizations can afford to lose

7. © 2021 IDERA, Inc. All rights reserved.
AGENT ALERTS
• Set up alerting to provide notification when database failures occur
• SQL Server agent sends notifications when it finds qualifying conditions
• Database engine errors, resource errors, and corruption errors
are important

8. © 2021 IDERA, Inc. All rights reserved.
QUERY PERFORMANCE
• Proper indexing is one of best performance enhancements you
can make to your database
• Database developers often use tools to create tables without
knowing much about good database design
• Look for highly-used, unused, fragmented, and missing indexes