3. SQL Administration tasks

• Objectives– Keep the databases long time running

• Contents– Update distribution statistics

– Rebuild indexes

– Maintain full-text indexes

– Alerts

– Maintenance Plan

• Practicals– Rebuild and update database indexes

– Making Alerts

– Making Maintenance Plan

• Summary

Updating Distribution Statistics• verify that the autocreate and

autoupdate statistics options are enabled (the default) for a database,

• right-click the database in SQL Server Enterprise Manager, click Properties, and then click the Options tab. Verify that both of the check boxes are selected.

• SQL query analyzer To manually update statistics on a table:

• SQL query analyzer To manually force create statistics on a table:

$ man man $ man –k tcp$ man passwd$ man 5 passwd

$ man man $ man –k tcp$ man passwd$ man 5 passwd

Update statistics northwind.dbo.customersUpdate statistics northwind.dbo.customers

Create statistics stats1 on northwind.dbo.customers (customerid) with fullscan, norecompute

Create statistics stats1 on northwind.dbo.customers (customerid) with fullscan, norecompute

• After a while, the database’s become fragmentated, this is normally defragmented automatically.

• Indexes control the order and placement of data stored in datapages of a table.

• Databases can become slow and start consume memory and cpu cycles.

• This makes the need for rebuilding indexes in databases regulary.

• Database Maintenance Plan Wizard in SQL Server Enterprise Manager.

• You can rebuild indexes using the Transact-SQL

Maintaining Indexes

Create index northwind_customers_idOn northwind.dbo.customers (customerid)Create index northwind_customers_idOn northwind.dbo.customers (customerid)

Drop index dbo.customers.northwind_customers_idDrop index dbo.customers.northwind_customers_id

Maintaining Full-Text Indexes

• Full-text indexes are indexes of all character data in one or more tables in a database.

• use the Full-Text Indexing Wizard in SQL Server Enterprise Manager to

– enable full-text indexing for a database, one or more tables, and specified columns within the tables.

• use the enterprice manager -> Database -> Full text catalog (right click) to

– New– Rebuild– Re populate – Remove

Double click or right click on any full text catalogue to change its properties/scheduling and so on

• The indexes are stored in the file system• Full text indexes must be populated with data from

databases/tables

Configuring event Alerts• Let the system speak to you!• SQL Server Event Alerts

– Error number. A unique number for each error.– Message string. Diagnostic information regarding the cause of the error, including the

object name– Severity. Low numbers indicate information messages and high numbers indicate serious

errors.– State code. Used by Microsoft support engineers to find the source code location for the

error.– Procedure name. The stored procedure name if the error occurred in a stored procedure.– Line number. The line number of a statement in a stored procedure that caused the error.– Performance Conditions. SQL Server 2000 provides objects and counters that are used

by Windows 2000 System Monitor• Configuring Alerts

– Using the Create Alert Wizard– Using SQL Server Enterprise Manager Directly

Management -> SQL Server Agent -> Alert (right click to make new or click on event)

• Responses– one or more operators can be notified using e-mail, pager, or NET SEND.– A custom notification message can be added– A specified– job can also be executed

New Alert from enterprice manager

Creating a Database Maintenance Plan

• Using the Database Maintenance Plan WizardThe Database Maintenance Plan Wizard allows you to configure the following tasks

to execute automatically according to specified schedules.

– Rebuilding indexes using a specified fill factor

– Shrinking a database to a specified size

– Updating distribution statistics

– Performing DBCC consistency checks

– Backing up database and transaction log files

– Setting up log shipping

• To start the Database Maintenance Plan Wizard, from the Tools menu:

1. click Database Maintenance Planner,

or in the console tree, right-click Database Maintenance Plans, in the Management container

2. then click New Maintenance Plan to display the Welcome To The Database Maintenance Plan Wizard page.

Viewing and Modifying Database Maintenance Plans

• After the database maintenance plan has been created, you can view and modify it in one of two ways.

• Management container in the instance

– expand the SQL Server Agent container, and then click the Jobs container.

• Using the Sqlmaint Utility– command-prompt utility can also be

used to create and execute a database maintenance plan.

– Microsoft recomen using the wizard