In this deck we look at some of the common maintenance tasks that you need to account for when dealing with a VLDB on SQL Server. Including backup & restore, index maintenance and integrity checking.

1. Managing VLDBs
Options to ease maintenance

2. About Me
John Q Martin
Sales Engineer for SQL Sentry
Over a decade of experience with SQL Server as a Dev,
DBA and BI Dev. Worked as a Premier Field Engineer
with Microsoft UK prior to joining SQL Sentry.
Twitter : @SQLDiplomat
Email : Jmartin@SQLSentry.com
Blog : http://blogs.sqlsentry.com/author/JohnMartin/

3. http://SQLSentry.com/BookJohn

4. http://www.sqlsentry.com/sql-server-books/
Free Resources

5. What is a VLDB? Very Large Database
 The context of what constitutes Very Large will vary,
depending on experience and what you are geared up to work
with. Ranging from Gigabytes to Terabytes.
Not to be confused with ‘Big Data’
 Related to the Volume, Variety, Velocity, and Veracity of data
being processed.

6. Typical
Management
Issues
Disaster Recovery Planning and
Implementation
Index and Statistics maintenance
Consistency checking
Performance Tuning

7. Disaster
Recovery
Planning
Clearly defined Recovery Time Objective (RTO) and
Recovery Point Objective (RPO) requirements are vital.
 No matter how well you tune a system, you will always run
into a bottleneck
Constantly reassess and test your plans around restore
capabilities for a VLDB.
 Backup performance will be monitored, restore performance is
not

8. Disaster
Recovery
Planning
There are a number of options available to you when it
comes to improving the performance of backups;
 Enable Compression
 Stripe Backup Files
 Isolate backup storage paths
 Modify BUFFERCOUNT, MAXTRANSFERSIZE and BLOCKSIZE
options for the BACKUP statement

9. Disaster
Recovery
Planning
SAN Snapshots are a double-edged sword;
 Yes : Snapshots are fast for large databases
 But : You are exposed while the snapshot is only on the SAN.
 But : You cannot perform a point in time restore, you can only
restore to a point in time…

10. Disaster
Recovery
Planning
SQL Server has additional backup options to help speed
things up.
 Differential
 File Group Backup
 File Backup
When using Enterprise Edition, piecemeal restores
mean that databases can be partially online.
 Architect your databases appropriately

11. Index & Stats
Maintenance Rebuilding large indexes can be prohibitive. From space
requirements for Online operations, to the duration
taken for offline operations.
Options for managing Index maintenance;
 Table Partitioning
 Online Index rebuilds
 Reorganize rather than Rebuild

12. Index & Stats
Maintenance Managing Statistics in VLDB scenarios can be
problematic for a number of reasons;
 Statistics Skew
 Auto-update threshold is disproportionate
 Size of tables means rebuilding with FULLSCAN is not an option
Options for managing statistics
 Trace Flag 2371
 Table Partitioning & Incremental Statistics (SQL 2014)

13. CHECKDB CHECKDB, while not a blocking process can saturate the
IO sub-system. For large databases this can also use a
lot of TempDB resources, and impact production
workloads.
Breaking CHECKDB down into is constituent parts
allows you to nibble through a consistency check.
 CHECKALLOC
 CHECKCATALOG
 CHECKTABLE

14. Performance
Tuning Understanding your workload is key to unlocking
performance;
 Are there any good candidates for table partitioning?
 What are the costs for the plans in cache
 Is your database schema correct
Leverage tracing and RML utilities to identify queries
that are being issued to the database.