SQL Server can obtain a very high level of performance with relatively little configuration tuning. You can obtain high levels of performance by using good application and database design, and not by extensive configuration tuning. See the "References" section of this article for information about how to troubleshoot various SQL Server performance issues. When you address a performance problem, the degree of improvement that is available from configuration tuning is typically modest unless you do not currently have the system properly configured. In SQL Server version 2000 and later, SQL Server uses automatic configuration tuning and it is extremely rare that configuration settings (especially advanced settings) need any changes. Generally, do not make a SQL Server configuration change without overwhelming reason and not without careful methodical testing to verify the need for the configuration change. You must establish a baseline before the configuration change so that you can measure the benefit after the change.
Alerts
An alert signifies when a given condition has been reached.
Checkpoint
The SQL Server processes in which data pages that have been modified are flushed to disk.
Collation sequence
Determines the order in which unicode data is sorted.
COM
Component Object Model is a model for APIs used to access data.
Compute by
A TSQL extension that allows you to have summary rows intermixed with detail rows.
Connection
A person or application that has logged onto SQL Server.
Data transformation service (DTS)
A SQL Server component that allows you to transfer data between multiple data sources.
DBCC
Database consistency checker - a set of utilities for verify a database and performing various system administrator tasks.
Deadlock
When two connections each hold locks on resources that the other connection wants.
Density
The number of rows in which a column has a given value.
Derived Columns
A calculated column. SQL Server allows you to define derived columns as part of the table definition.
Dirty page
A memory page in which data has been changed.
Errorlog
The OS file that SQL Server writes errors and messages to.
Event
A significant occurrence.
Event category
A group of events.
Event class
A group of events.
Event log
The windows NT logging mechanism.
Extended stored procedures
SQL Server stored procedures that access external DLLs.
Extent
SQL Server allocation unit. An extent is 8 data pages.
Filter
Limits what is viewed.
Fragmentation
A condition that occurs when data is not stored consecutively.
Hard paging
When the data used by an application is on the swap file.
Hetrogeneous data sources
Data that is stored by a different RDBMS.
Histogram
A range of values within an index.
Homogeneous data sources
Data that is stored by the same RDBMS.
Identity column
An automatically incrementing column.
Index Tuning Wizard
A wizard that helps you develop the correct indexes .for a table.
Jobs
A SQL Server agent set of tasks.
Latches
A light weight object that does not need to be locked.
Leaf page
The lowest level of an index.
Least recently used (LRU)
The in memory data page that has gone the longest time without being accessed.
Linked servers
OLE-DB connection to external data sources.
Lock
A SQL Server mechanism use to ensure transaction isolation levels.
MAPI
Mail Application Programming Interface - An interface that Microsoft uses to send and read mail.
Master server
In a multi server SQL Server Agent environment, a master server is the server that stores the SQL Server Agent information.
MIB
Management Information Bulletin - A SNMP component that describes the information that can be monitored.
Microsoft Repository
A set of Microsoft ActiveX interfaces and data models that are used to define database schema and data transformations as specified by the Microsoft Data Warehousing Framework.
Most recently used (MRU)
The in memory data page that was the last data page to be accessed.
msdb
The system database that is used to store SQL Server Agent information and DTS information.
OLE-DB
A COM API that allows you to access data sources.
Operators
A person that gets notified when an alert occurs.
Package
A set of DTS commands used to transform data.
POP3
A standard mail interface.
Procedure cache
The amount of memory that SQL Server reserves for storing stored procedures.
Registry
A repository for application and system configuration information.
Remote procedure calls(RPC)
A means of communicating between two SQL Servers.
Scalar functions
A function that returns a single value.
Single user mode
A database that is configured to allow only one user to access it.
SNMP
Simple Network Management Protocol- a protocol for monitoring and managing network components.soft paging Removing data from
the page cache.
Soft paging
Removing data from the page cache.
SQL Mail
SQL Server's interface to your e-mail system.
SQL Server Agent
A SQL Sever component that allows you to schedule jobs, define alerts, and define operators.
SQL-DMO
An API that allows you to access SQL Server's Data Management Objects.
Statistics
Track the data distribution.
System catalog table
A system wide table, stored in the master database, that tracks system resources.
System stored procedure
A procedure stored in the master database which begins with sp_ that is used to perform system functions.
Target server
In a multi server SQL Server Agent environment, this is a server that a job will run against.
Task
One of the steps in a job.
Trace
The information that SQL Server profiler gathers.
trace flags
A SQL Server dbcc option that changes the behavior of SQL Server.
Trace Wizard
A SQL Server wizard that helps you set up a trace.
Trigger
Code that is executed in response to a database event, or in response to a SQL statement issued against a table.
Workflow
Describes the steps need top be done to complete a task.