Lesson 4: Using DBCC CHECKDB in .NET

Encode PDF-417 2d barcode in .NET Lesson 4: Using DBCC CHECKDB

Lesson 4: Using DBCC CHECKDB
Drawing PDF417 In .NET Framework
Using Barcode drawer for .NET framework Control to generate, create PDF417 image in Visual Studio .NET applications.
www.OnBarcode.com
Scanning PDF 417 In Visual Studio .NET
Using Barcode reader for .NET framework Control to read, scan read, scan image in .NET applications.
www.OnBarcode.com
Lesson 4: Using DBCC CHECKDB
Paint Bar Code In .NET Framework
Using Barcode printer for .NET Control to generate, create bar code image in .NET framework applications.
www.OnBarcode.com
Bar Code Reader In .NET
Using Barcode scanner for .NET framework Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
As part of your regular database maintenance, you need to check your databases for integrity issues. To help you complete this task, SQL Server 2005 provides the DBCC CHECKDB database console command. DBAs need to become familiar with this command, its uses, and its output to ensure the stability of their databases. This lesson gives you an overview of DBCC CHECKDB and some tips about using it to check the integrity of your database.
PDF-417 2d Barcode Creator In C#
Using Barcode maker for VS .NET Control to generate, create PDF417 image in .NET framework applications.
www.OnBarcode.com
PDF-417 2d Barcode Maker In VS .NET
Using Barcode drawer for ASP.NET Control to generate, create PDF 417 image in ASP.NET applications.
www.OnBarcode.com
After this lesson, you will be able to:
Encoding PDF-417 2d Barcode In Visual Basic .NET
Using Barcode creation for VS .NET Control to generate, create PDF-417 2d barcode image in .NET framework applications.
www.OnBarcode.com
Create PDF 417 In Visual Studio .NET
Using Barcode encoder for .NET framework Control to generate, create PDF417 image in VS .NET applications.
www.OnBarcode.com
Perform database integrity checks by using the DBCC CHECKDB command.
UCC - 12 Generation In VS .NET
Using Barcode maker for .NET Control to generate, create UCC - 12 image in Visual Studio .NET applications.
www.OnBarcode.com
Code 128A Printer In VS .NET
Using Barcode drawer for .NET Control to generate, create Code128 image in Visual Studio .NET applications.
www.OnBarcode.com
Estimated lesson time: 15 minutes
Matrix Barcode Generator In .NET Framework
Using Barcode maker for .NET Control to generate, create 2D Barcode image in .NET framework applications.
www.OnBarcode.com
Planet Generation In Visual Studio .NET
Using Barcode creation for .NET framework Control to generate, create Planet image in .NET applications.
www.OnBarcode.com
DBCC CHECKDB
Scanning UPC Symbol In None
Using Barcode decoder for Software Control to read, scan read, scan image in Software applications.
www.OnBarcode.com
Print PDF-417 2d Barcode In None
Using Barcode generator for Font Control to generate, create PDF417 image in Font applications.
www.OnBarcode.com
The DBCC CHECKDB command performs a variety of checks on the database you issue it against to verify the allocation, structural integrity, and logical integrity of all objects in the database. You need to become familiar with the command and the checks that it issues so that you use the appropriate options and so that you don t duplicate the checks it performs during the often-limited maintenance windows found in today s database environment. The DBCC CHECKDB statement performs the following integrity checks:
Encoding QR Code 2d Barcode In None
Using Barcode encoder for Font Control to generate, create QR-Code image in Font applications.
www.OnBarcode.com
Code-128 Drawer In Java
Using Barcode generation for Java Control to generate, create Code128 image in Java applications.
www.OnBarcode.com
Issues DBCC CHECKALLOC on the database Issues DBCC CHECKTABLE on every table and view in the database Issues DBCC CHECKCATALOG on the database Validates Service Broker data in the database Validates the contents of every indexed view in the database
QR Code ISO/IEC18004 Maker In None
Using Barcode maker for Excel Control to generate, create QR Code 2d barcode image in Microsoft Excel applications.
www.OnBarcode.com
Drawing Bar Code In Java
Using Barcode printer for Eclipse BIRT Control to generate, create bar code image in Eclipse BIRT applications.
www.OnBarcode.com
DBCC CHECKDB
PDF417 Decoder In Java
Using Barcode scanner for Java Control to read, scan read, scan image in Java applications.
www.OnBarcode.com
QR Code Creation In VS .NET
Using Barcode drawer for ASP.NET Control to generate, create QR Code ISO/IEC18004 image in ASP.NET applications.
www.OnBarcode.com
MORE INFO
To see all the many options available with the DBCC CHECKDB command, see the SQL Server 2005 Books Online topic DBCC CHECKDB (Transact-SQL).
12
Using Transact-SQL to Manage Databases
DBAs should keep in mind the following best practices associated with running DBCC CHECKDB:
Because of the time DBCC CHECKDB can take to run against larger databases, you should execute the command with the PHYSICAL_ONLY option if you are doing frequent checks on production systems. PHYSICAL_ONLY provides a small-overhead check of the physical consistency of the database and can detect torn pages, checksum failures, and common hardware failures that can compromise a user s data. To get a full integrity check of your database, periodically execute DBCC CHECKDB with no options specified so that you don t limit the check. When errors are reported during the execution of DBCC CHECKDB, restore the database from a recent database backup chain to resolve the issues. If the database cannot be restored because of its size, a lack of valid database backups, or other issues, consider executing the DBCC CHECKDB command by using one of the command s repair options: REPAIR_ALLOW_DATA_LOSS, REPAIR_FAST, or REPAIR_REBUILD. However, using a repair option, which specifies that DBCC CHECKDB should repair the found issues, should be a last resort because repair operations do not consider any constraints that might exist on or between tables.
Repair options require single-user mode
NOTE
Note that to use one of the three repair options of DBCC CHECKDB, the specified database must be in single-user mode.
Quick Check
What other DBCC statements does the DBCC CHECKDB statement execute The DBCC CHECKDB statement executes the following DBCC statements: DBCC CHECKALLOC, DBCC CHECKTABLE, and DBCC CHECKCATALOG.
Quick Check Answer
PRACTICE
Executing the DBCC CHECKDB Statement
The following two practices will walk you through the process of executing a DBCC CHECKDB statement to ensure database integrity and using that statement to repair any integrity issues found.
Lesson 4: Using DBCC CHECKDB
Practice 1: Execute DBCC CHECKDB to Review Integrity Issues
In this practice, you execute the DBCC CHECKDB statement and review the output for database integrity issues. 1. If necessary, start SSMS and connect to the instance containing the AdventureWorks sample database. Open the Query Editor pane. 2. In the Query Editor pane, type the following Transact-SQL statement to execute the DBCC CHECKDB statement:
USE master; --Check for database integrity issues. --Show all error messages. DBCC CHECKDB ( AdventureWorks ) WITH ALL_ERRORMSGS;
3. Scroll down the output from the statement to review any error messages.
Practice 2: Execute DBCC CHECKDB to Review Integrity Issues and Allow for Issue Correction
In this practice, you execute the DBCC CHECKDB statement and allow the statement to correct integrity issues. 1. If necessary, start SSMS and connect to the instance containing the AdventureWorks sample database. Open the Query Editor pane. 2. In the Query Editor pane, type the following Transact-SQL statements to set the database to single-user mode, execute the DBCC CHECKDB statement, and allow the statement to attempt to repair any issues found:
USE master; --Check for database integrity issues. --Allow the statement to attempt to repair issues with possible loss of data. --Show all error messages. --Database must be in single-user mode. ALTER DATABASE AdventureWorks SET SINGLE_USER; DBCC CHECKDB ( AdventureWorks , REPAIR_ALLOW_DATA_LOSS ) WITH ALL_ERRORMSGS;
3. Scroll down the output from the statement to review any error messages. 4. In the Query Editor pane, type the following Transact-SQL statement to execute the following statement to set the database back to multiple-user mode:
--Remove from single-user mode. ALTER DATABASE AdventureWorks SET MULTI_USER;
Copyright © OnBarcode.com . All rights reserved.