Glossary

3 4

A

ACID properties

The four properties (atomicity, consistency, isolation, durability) of a transaction. Atomicity means that all of a transaction s data modifications are performed, or none of them is performed. Consistency means that all data must be left in a consistent state. Isolation means that modifications made by concurrent transactions must be isolated from the modifications made by any other concurrent transactions. Durability means that the effects of a transaction must be permanent (even after a system failure).

active statement

A SQL statement that has been executed but whose result set has not yet been canceled or fully processed.

ActiveX Data Objects

(ADO)

An easy-to-use application programming interface (API) that wraps OLE DB for use in languages such as Visual Basic, Visual Basic for Applications, Active Server Pages (ASP), and Microsoft Internet Explorer Visual Basic Scripting.

ActiveX Data Objects (Multidimensional)

(ADO MD)

A high-level, language-independent set of object-based data access interfaces optimized for multidimensional data applications. Visual Basic and other automation languages use ADO MD as the data access interface to multidimensional data storage. ADO MD is a part of ADO 2.0 and later.

ADO

See ActiveX Data Objects

ADO MD

See ActiveX Data Objects (Multidimensional) (ADO MD)

alert

A user-defined response to a SQL Server event. Alerts can either execute a defined task or send an e-mail, pager, or NET SEND message to a specified operator.

American National Standards Institute

(ANSI)

An organization of American industry and business groups that develops trade and communication standards for the United States. Through membership in the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC), ANSI coordinates American standards with corresponding international standards.

Analysis Server

The server component of Analysis Services that is specifically designed to create and maintain multidimensional data structures and provide multidimensional data in response to client queries.

anonymous subscription

An anonymous subscription is a type of pull subscription for which detailed information about the subscription and the Subscriber is not stored.

ANSI

See American National Standards Institute (ANSI)

ANSI-to-OEM conversion

The conversion of characters that must occur when data is transferred from a database that stores character data using a specific code page to a client application on a computer that uses a different code page. Typically, Windows-based client computers use ANSI/ISO code pages, and some databases (for compatibility reasons) might use OEM code pages, such as the MS-DOS 437 code page or code page 850.

API

See application programming interface (API)

API server cursor

A server cursor built to support the cursor functions of an application programming interface (API), such as ODBC, OLE DB, ADO, and DB-Library. An application does not usually request a server cursor directly; it calls the cursor functions of the API. The SQL Server interface for that API implements a server cursor if that is the best way to support the requested cursor functionality. See also server cursor

application programming interface

(API)

A set of routines available in an application, such as ADO, for use by software programmers when designing an application interface.

application role

A SQL Server role created to support the security needs of an application.

article

An object specified for replication. An article is a component in a publication and can be a table, specified columns (using a column filter), specified rows (using a row filter ), a stored procedure or view definition, the execution of a stored procedure, a view, an indexed view, or a user-defined function.

atomic

Either all of the transaction data modifications are performed or none of them are performed.

authentication

The process of validating that the user attempting to connect to SQL Server is authorized to do so. See also SQL Server authentication

authorization

The operation that verifies the permissions and access rights granted to a user.

automatic recovery

Recovery that occurs every time SQL Server is restarted. Automatic recovery protects your database if there is a system failure.

autonomy

The independence one site has from other sites when performing modifications to data.

B

backup

A copy of a database, transaction log, file, or filegroup used to recover data after a system failure.

backup device

A tape or disk used in a backup or restore operation.

backup file

A file that stores a full or partial database, transaction log, or file and/or filegroup backup.

backup media

The tape, disk, or named pipe used to store a backup set.

base data type

Any system-supplied data type, for example, char, varchar, binary, and varbinary. User-defined data types are derived from base data types. See also data type

batch

A set of SQL statements submitted together and executed as a group. A script is often a series of batches submitted one after the other.

Bcp files

Files that store bulk copy data created by the bulk copy utility or synchronization.

Bcp utility

See Bulk Copy (Bcp) Utility

Bulk Copy (Bcp) Utility

A command-prompt bulk copy utility that copies SQL Server data to or from an operating system file in a user-specified format.

built-in functions

A group of predefined functions provided as part of the Transact-SQL and Multidimensional Expressions (MDX) languages.

business rules

The logical rules that are used to run a business. Business rules can be enforced in the .com objects that make up the middle tier of a Windows DNA system; they can also be enforced in a SQL Server database using triggers, stored procedures, and constraints.

C

CA

See certification authority (CA)

cache aging

The mechanism of caching that determines when a cache row is outdated and must be refreshed.

calculated column

A column in a table that displays the result of an expression rather than stored data. For example, CalculatedCostColumn = Price * Quantity.

calculated field

A field defined in a query that displays the result of an expression rather than stored data.

call-level interface (CLI)

The interface supported by ODBC for use by an application.

cascading delete

An operation that deletes a row containing a primary key value that is referenced by foreign key columns in existing rows in other tables. On a cascading delete, all of the rows whose foreign key values reference the deleted primary key value are also deleted.

cascading update

An operation that updates a primary key value that is referenced by foreign key columns in existing rows in other tables. On a cascading update, all of the foreign key values are updated to match the new primary key value.

catalog (database)

See database catalog

catalog (system)

See system catalog

certificate

A collection of data used for authentication and secure exchange of information on nonsecured networks, such as the Internet. A certificate securely binds a public encryption key to the entity that holds the corresponding private encryption key. Certificates are digitally signed by the issuing certification authority and can be managed for a user, a computer, or a service.

certification authority

(CA)

An entity responsible for establishing and vouching for the authenticity of public keys belonging to users (end entities) or other certification authorities. Activities of a certification authority may include binding public keys to distinguished names through signed certificates, managing certificate serial numbers and certificate revocation.

character format

Data stored in a bulk copy data file using text characters. See also native format

character set

A character set determines the types of characters that SQL Server recognizes in the char, varchar, and text data types. Each character set is a set of 256 letters, digits, and symbols specific to a country or language. The printable characters of the first 128 values are the same for all character sets. The last 128 characters, sometimes referred to as extended characters, are unique to each character set. A character set is related to, but separate from, Unicode characters.

CHECK constraints

A constraint that defines which data values are acceptable in a column. You can apply CHECK constraints to multiple columns, and you can apply multiple CHECK constraints to a single column. When a table is dropped, CHECK constraints are also dropped.

checkpoint

An event in which the database engine writes dirty buffer pages to disk. Dirty pages are pages that have been modified, but the modifications have not yet been written to disk. Each checkpoint writes to disk all pages that were dirty at the last checkpoint and still have not been written to disk. Checkpoints occur periodically based on the number of log records generated by data modifications, or when requested by a user or a system shutdown.

CLI

See call-level interface (CLI)

client cursor

A cursor implemented on the client. The entire result set is first transferred to the client, and the client application programming interface (API) software implements the cursor functionality from this cached result set.

clustered index

An index in which the logical order of the key values determines the physical order of the corresponding rows in a table.

code page

For character and Unicode data, a definition of the bit patterns that represent specific letters, numbers, or symbols (such as 0x20 representing a blank space and 0x74 representing the character "t"). Some data types use 1 byte per character; each byte can have 1 of 256 different bit patterns.

collation

A set of rules that determine how data is compared, ordered, and presented. Character data is sorted using collation information, including locale, sort order, and case sensitivity. See also locale, SQL collation

column

In a SQL table, the area in each row that stores the data value for some attribute of the object modeled by the table. For example, the Employees table in the Northwind sample database models the employees of the Northwind Traders company. The LastName column in each row of the Employees table stores the last name of the employee represented by that row, the same way a LastName field in a window or form would contain a last name. See also row

column filter

Column filters restrict the columns to be included as part of a snapshot, transactional, or merge publication.

column-level collation

The ability of SQL Server 2000 to support multiple collations in a single instance. Databases can have default collations different from the default collation of the instance. Individual columns and variables can be assigned collations different from the default collation for the instance or database. Each column in a table can have a different collation.

column-level constraint

A constraint definition that is specified within a column definition when a table is created or altered. The constraint applies only to the associated column. See also constraint

COM

See Component Object Model (COM)

COM-structured storage file

A component object model (COM) compound file used by Data Transformation Services (DTS) to store the version history of a saved DTS package.

commit

An operation that saves all changes to databases made since the start of a transaction. A commit guarantees that all of the transaction's modifications are made a permanent part of the database. A commit also frees resources, such as locks, used by the transaction. See also roll back

Component Object Model

(COM)

A Microsoft specification for developing component software. Several SQL Server and database application programming interfaces (APIs) such as SQL-DMO, OLE DB, and ADO are based on COM. Some SQL Server components, such as Analysis Services and English Query, store objects as COM objects. See also method

composite index

An index that uses more than one column in a table to index data.

composite key

A key composed of two or more columns.

computed column

A virtual column in a table whose value is computed at run time. The values in the column are not stored in the table, but are computed based on the expression that defines the column. An example of the definition of a computed column is: Cost as Price * Quantity.

concurrency

A process that allows multiple users to access and change shared data at the same time. SQL Server uses locking to allow multiple users to access and change shared data at the same time without conflicting with each other.

connection

An interprocess communication (IPC) linkage established between a SQL Server 2000 application and an instance of SQL Server 2000. The connection is a network link if the application is on a computer different from the SQL Server 2000 instance. If the application and the SQL Server 2000 instance are on the same computer, the linkage is formed through a local IPC mechanism, such as shared memory. The application uses the IPC linkage to send Transact-SQL statements to SQL Server and to receive result sets, errors, and messages from SQL Server.

constraint

A property assigned to a table column that prevents certain types of invalid data values from being placed in the column. For example, a UNIQUE or PRIMARY KEY constraint prevents you from inserting a value that is a duplicate of an existing value, a CHECK constraint prevents you from inserting a value that does not match a search condition, and NOT NULL prevents you from inserting a NULL value. See also column-level constraint

continuation media

The backup media used when the initial medium becomes full, allowing continuation of the backup operation.

CPU busy

A SQL Server statistic that reports the time, in milliseconds, the central processing unit (CPU) spent on SQL Server work.

cube

A set of data that is organized and summarized into a multidimensional structure. See also multidimensional structure

cursor

An entity that maps over a result set and establishes a position on a single row within the result set. After the cursor is positioned on a row, operations can be performed on that row, or on a block of rows starting at that position. The most common operation is to fetch (retrieve) the current row or block of rows.

D

data block

In text, ntext, and image data, a data block is the unit of data transferred at one time between an application and an instance of SQL Server 2000. The term is also applied to the units of storage for these data types. In tape backup files, data block is the unit of physical I/O.

data connection

A collection of information required to access a specific database. The collection includes a data source name and logon information. Data connections are stored in a project and are activated when the user performs an action that requires access to the database. For example, a data connection for a SQL Server database consists of the name of the database, the location of the server on which it resides, network information used to access that server, and a user ID and password.

Data Control Language

(DCL)

The subset of SQL statements used to control permissions on database objects. Permissions are controlled using the GRANT and REVOKE statements.

data definition

The process of specifying the attributes, properties, and objects in a database.

data definition language

(DDL)

A language, usually part of a database management system, that is used to define all attributes and properties of a database, especially row layouts, column definitions, key columns (and sometimes keying methodology), file locations, and storage strategy.

data dictionary

A set of system tables, stored in a database catalog, that includes definitions of database structures and related information, such as permissions.

data dictionary view

A system table.

data file

In bulk copy operations, the file that transfers data from the bulk copy out operation to the bulk copy in operation. In SQL Server 2000 databases, data files hold the data stored in the database. Every SQL Server 2000 database has at least one primary data file, and can optionally have multiple secondary data files to hold data that does not fit on the primary data file. See also log file

data integrity

A state in which all the data values stored in the database are correct. If incorrect data values have been stored in a database, the database is said to have lost data integrity.

data lineage

Information used by Data Transformation Services (DTS), in conjunction with Meta Data Services, that records the history of package execution and data transformations for each piece of data.

data manipulation language

(DML)

The subset of SQL statements used to retrieve and manipulate data.

data mart

A subset of the contents of a data warehouse. A data mart tends to contain data focused at the department level, or on a specific business area. See also data warehouse

data modification

An operation that adds, deletes, or changes information in a database using Transact-SQL statements such as INSERT, DELETE, and UPDATE.

data pump

An OLE DB service provider that provides the infrastructure to import, export, and transform data between heterogeneous data stores using Data Transformation Services (DTS).

data scrubbing

Part of the process of building a data warehouse out of data coming from multiple online transaction processing (OLTP) systems. The process must address errors such as incorrect spellings, conflicting spelling conventions between two systems, and conflicting data (such as having two part numbers for the same part).

data source

In ADO and OLE DB, the location of a source of data exposed by an OLE DB provider. See also ODBC data source

data source name

(DSN)

The name assigned to an ODBC data source. Applications can use DSNs to request a connection to a system ODBC data source, which specifies the computer name and (optionally) the database to which the DSN maps.

Data Transformation Services

(DTS)

The SQL Server tool for transferring and transforming data between disparate data sources.

data type

An attribute that specifies what type of information can be stored in a column, parameter, or variable. System-supplied data types are provided by SQL Server; user-defined data types can also be created. See also base data type

data warehouse

A database specifically structured for query and analysis. A data warehouse typically contains data representing the business history of an organization. See also fact table

database

A collection of information, tables, and other objects organized and presented to serve a specific purpose, such as searching, sorting, and recombining data. Databases are stored in files.

database catalog

The part of a database that contains the definition of all the objects in the database, as well as the definition of the database. See also system catalog

database diagram

A graphical representation of the objects in a database. A database diagram can be either a whole or a partial picture of the structure of a database; it includes objects for tables, the columns they contain, and the relationship between them.

database file

One of the physical files that make up a database.

database language

The language used for accessing, querying, updating, and managing data in relational database systems. Structured Query Language (SQL) is a widely used database language. The Microsoft SQL Server implementation of SQL is called Transact-SQL.

database object

A database component. A table, index, trigger, view, key, constraint, default, rule, user-defined data type, or stored procedure in a database. May also refer to a database.

database owner

A member of the database administrator role of a database. There is only one database owner. The owner has full permissions in that database and determines the access and capabilities provided to other users.

database schema

The names of tables, fields, data types, and primary and foreign keys of a database. Also known as the database structure.

database script

A collection of statements used to create database objects. Transact-SQL scripts are saved as files, usually ending with .sql.

Db-Lib

See DB-Library (DB-Lib)

DB-Library

(DB-Lib)

A series of high-level language (including C) libraries that provide the application programming interface (API) for the client in a client/server system. Supported only for backward compatibility.

DCL

See Data Control Language (DCL)

DDL

See data definition language (DDL)

deadlock

A situation in which two users, each having a lock on one piece of data, attempt to acquire a lock on the other's piece. Each user would wait indefinitely for the other to release the lock, unless one of the user processes is terminated. SQL Server detects deadlocks and terminates one user's process. See also livelock

decision support

Systems designed to support the complex analytic analysis required to discover business trends. The information retrieved from these systems allows managers to make business decisions based on timely and accurate analysis of business trends.

declarative referential integrity

(DRI)

FOREIGN KEY constraints defined as part of a table definition that enforce proper relationships between tables. The constraints ensure that proper actions are taken when DELETE, INSERT, and UPDATE statements remove, add, or modify primary or foreign key values. The DRI actions enforced by FOREIGN KEY constraints can be supplemented with additional referential integrity logic defined in triggers on a table.

default

A data value, option setting, collation, or name assigned automatically by the system if a user does not specify the value, setting, collation, or name. An action taken automatically at certain events if a user has not specified the action to take.

DEFAULT constraint

A property defined for a table column that specifies a constant to be used as the default value for the column. If any subsequent INSERT or UPDATE statement specifies a value of NULL for the column, or does not specify a value for the column, the constant value defined in the DEFAULT constraint is placed in the column.

default database

The database the user is connected to immediately after logging in to SQL Server.

default instance

The copy of SQL Server that uses the computer name on which it is installed as its name. See also named instance, multiple instances

default language

The language that SQL Server 2000 uses for errors and messages if a user does not specify a language. Each SQL Server 2000 login has a default language.

delimiter

In Transact-SQL, characters that indicate the start and end of an object name, using either double quotation marks ("") or brackets ([]).

denormalize

To introduce redundancy into a table in order to incorporate data from a related table. The related table can then be eliminated. Denormalization can improve efficiency and performance by reducing complexity in a data warehouse schema. See also schema

deny

To remove a permission from a user account and prevent the account from gaining permission through membership in groups or roles within the permission.

dependencies

The views and procedures that depend on the specified table or view.

device

See file

differential database backup

A database backup that records only those changes made to the database since the last full database backup. A differential backup is smaller, is faster to restore than a full backup, and has minimal effect on performance.

direct response mode

The default mode in which SQL Server statistics are gathered separately from the SQL Server Statistics display. Data is available immediately to SQL Server Performance Monitor; however, the statistics displayed are one period behind the statistics retrieved.

dirty pages

Buffer pages that contain modifications that have not been written to disk.

dirty read

Reads that contain uncommitted data. For example, transaction1 changes a row. Transaction2 reads the changed row before transaction1 commits the change. If transaction1 rolls back the change, transaction2 has read a row that never logically existed.

distribute

To move transactions or snapshots of data from the Publisher to Subscribers, where they are applied to the destination tables in the subscription databases.

distributed query

A single query that accesses data from multiple data sources.

distribution database

A database on the Distributor that stores data for replication including transactions, snapshot jobs, synchronization status, and replication history information.

distribution retention period

The distribution retention period determines the amount of information stored for a replication agent and the length of time subscriptions will remain active in the distribution database. When the distribution retention period is exceeded, the Distribution Clean Up Agent runs.

Distributor

A server for SQL Server replication that hosts the distribution database and stores history data, and/or transactions and metadata. See also local Distributor, remote Distributor

DML

See data manipulation language (DML)

domain

In Windows 2000 security, a collection of computers grouped for viewing and administrative purposes that share a common security database. In relational databases, the set of valid values allowed in a column.

domain integrity

An integrity mechanism that enforces the validity of entries for a given column. The mechanism, such as the CHECK constraint, can restrict the possible data values by data type, format, or range of values allowed.

DRI

See declarative referential integrity (DRI)

DSN

See data source name (DSN)

DTS

See Data Transformation Services (DTS)

DTS package

An organized collection of connections, Data Transformation Services (DTS) tasks, DTS transformations, and workflow constraints defined by the DTS object model and assembled either with a DTS tool or programmatically.

DTS package template

A model Data Transformation Services (DTS) package. The template is used to help create and configure a particular type of package.

dump

See backup

dump file

See backup file

dynamic filter

Merge replication filters that restrict data based on a system function or user-defined function (for example: SUSER_SNAME()).

dynamic locking

The process used by SQL Server to determine the most cost-effective locks to use at any one time.

dynamic recovery

The process that detects and/or attempts to correct software failure or loss of data integrity within a relational database management system (RDBMS).

dynamic snapshot

A snapshot of a merge publication with dynamic filters that is applied using bulk copy files to improve performance.

E

encryption

A method for keeping sensitive information confidential by changing data into an unreadable form.

English Query

Refers to a Microsoft application development product that allows users to ask questions in English, rather than in a computer language such as SQL. For example, you might ask, "How many customers bought products last year?" rather than prepare an equivalent SQL statement.

error log

A text file that records system information from SQL Server.

error state number

A number associated with SQL Server 2000 messages that helps Microsoft support engineers find the specific code location that issued the message. This can be helpful in diagnosing errors that may be generated from multiple locations in the SQL Server 2000 code.

exclusive lock

A lock that prevents any other transaction from acquiring a lock on a resource until the original lock on the resource is released at the end of the transaction. An exclusive lock is always applied during an update operation (INSERT, UPDATE, or DELETE).

explicit transaction

A group of SQL statements enclosed within transaction delimiters. The first delimiter must be either BEGIN TRANSACTION or BEGIN DISTRIBUTED TRANSACTION, and the end delimiter must be one of the following: COMMIT TRANSACTION, COMMIT WORK, ROLLBACK TRANSACTION, ROLLBACK WORK, SAVE TRANSACTION.

extended stored procedure

A function in a dynamic-link library (DLL) that is coded using the SQL Server 2000 Extended Stored Procedure API. The function can then be invoked from Transact-SQL using the same statements that are used to execute Transact-SQL stored procedures. Extended stored procedures can be built to perform functionality not possible with Transact-SQL stored procedures.

extent

The unit of space allocated to a SQL Server object, such as a table or index, whenever the object needs more space. In SQL Server 2000, an extent is eight contiguous pages.

F

fact table

A central table in a data warehouse schema.

field

An area in a window or record that stores a single data value. Some databases, such as Microsoft Access, use field as a synonym for column.

field length

In bulk copy, the maximum number of characters needed to represent a data item in a bulk copy character format data file.

field terminator

In bulk copy, one or more characters marking the end of a field or row, separating one field or row in the data file from the next.

file

In SQL Server databases, a basic unit of storage for a database. One database can be stored in several files. SQL Server uses three types of files: data files (which store data), log files (which store transaction logs), and backup files (which store backups of a database).

file DSN

Stores connection information for a database in a file that is saved on your computer. The file is a text file with the extension .dsn. The connection information consists of parameters and corresponding values that the ODBC Driver Manager uses to establish a connection.

file storage type

Defines the storage format used in the data file that transfers data from a bulk copy out operation to a bulk copy in operation. In native mode files, all data is stored using the same internal structures that SQL Server 2000 uses to store the data in a database. In character mode files, all data is converted to character strings.

filegroup

In SQL Server, a named collection of one or more files that forms a single unit of allocation or for administration of a database.

fill factor

An attribute of an index that defines the amount of free space on each page of the index. FILLFACTOR accommodates future expansion of table data and reduces the potential for page splits. FILLFACTOR is a value from 1 through 100 that specifies the percentage of the index page to be left empty.

filter

A set of criteria that control the set of records returned as a result set. Filters can also define the sequence in which rows are returned.

filtering

The ability to restrict data based upon criteria set in the WHERE clause of a SQL statement. For replication, filtering occurs on table articles defined in a publication. The result is partitions of data that can be published to Subscribers. See also partitioning, vertical filtering

fixed database role

A predefined role that exists in each database. The scope of the role is limited to the database in which it is defined.

fixed server role

A predefined role that exists at the server level. The scope of the role is limited to the SQL Server instance in which it is defined.

FK

See foreign key (FK)

foreign key

(FK)

The column or combination of columns whose values match the primary key (PK) or unique key in the same or another table. Also called the referencing key.

foreign table

A table that contains a foreign key.

fragmentation

Occurs when data modifications are made. You can reduce fragmentation and improve read-ahead performance by dropping and re-creating a clustered index.

full-text catalog

Stores all of the full-text indexes for tables within a database.

full-text enabling

The process of allowing full-text querying to occur on the current database.

full-text index

The portion of a full-text catalog that stores all of the full-text words and their locations for a given table.

full-text query

As a SELECT statement, a query that searches for words, phrases, or multiple forms of a word or phrase in the character-based columns (of char, varchar, text, ntext, nchar, or nvarchar data types). The SELECT statement returns those rows meeting the search criteria.

full-text service

The SQL Server component that performs the full-text querying.

function

A piece of code that operates as a single logical unit. A function is called by name, accepts optional input parameters, and returns a status and optional output parameters. Many programming languages support functions, including C, Visual Basic, and Transact-SQL. Transact-SQL supplies built-in functions, which cannot be modified, and supports user-defined functions, which can be created and modified by users.

G

global default

A default that is defined for a specific database and is shared by columns of different tables.

global rule

A rule that is defined for a specific database and is shared by columns of different tables.

global subscriptions

A subscription to a merge publication with an assigned priority value used for conflict detection and resolution.

grant

Applies permissions to a user account, which allows the account to perform an activity or work with data.

guest

A special user account that is present in all SQL Server 2000 databases and cannot be removed from any database. If a connection is made using a login that has not been assigned a user account in a database and the connection references objects in that database, it has the permissions assigned only to the guest account in that database.

H

heterogeneous data

Data stored in multiple formats. For example, data stored in a SQL Server database, a text file, and an Excel spreadsheet.

homogeneous data

Data that comes from multiple data sources that are all managed by the same software (for example, data that comes from several Excel spreadsheets, or data that comes from several SQL Server 2000 instances). A SQL Server 2000 distributed query is homogeneous if all the data comes from SQL Server 2000 instances.

horizontal partitioning

To segment a single table into multiple tables based on selected rows. Each of the multiple tables has the same columns but fewer rows. See also partitioning

HTML

See Hypertext Markup Language (HTML)

Hypertext Markup Language

(HTML)

A system of marking up, or tagging, a document so that it can be published on the World Wide Web (WWW). Documents prepared in HTML include reference graphics and formatting tags. You use a Web browser (such as Microsoft Internet Explorer) to view these documents.

I

identifier

The name of an object in a database. An identifier can be from 1 through 128 characters.

identity column

A column in a table that has been assigned the identity property. The identity property generates unique numbers.

identity property

A property that generates values that uniquely identify each row in a table. When inserting rows into a table that has an identity column, SQL Server generates the next identity value automatically based on the last used identity value and the increment value specified during column creation.

idle time

A SQL Server 2000 Agent condition that defines the level of CPU usage by the SQL Server 2000 database engine that constitutes an idle state. SQL Server 2000 Agent jobs can then be created to run whenever the database engine CPU usage falls below the level defined in the idle time definition. This minimizes the impact the SQL Server Agent jobs may have on other tasks accessing the database.

IEC

See International Electrotechnical Commission (IEC)

immediate updating

An option available with snapshot replication and transactional replication that allows data modifications to be made to replicated data at the Subscriber. The data modifications are then immediately propagated to the Publisher using two-phase commit protocol (2PC).

immediate updating Subscribers

See immediate updating subscriptions

immediate updating subscriptions

A subscription to a snapshot or transactional publication for which the user is able to make data modifications at the Subscriber. The data modifications are then immediately propagated to the Publisher using two-phase commit protocol (2PC).

implicit transaction

A connection option in which each SQL statement executed by the connection is considered a separate transaction.

implied permission

Permission to perform an activity specific to a role. Implied permissions cannot be granted, revoked, or denied.

index

In a relational database, a database object that provides fast access to data in the rows of a table, based on key values. Indexes can also enforce uniqueness on the rows in a table. SQL Server supports clustered and nonclustered indexes. The primary key of a table is automatically indexed. In full-text search, a full-text index stores information about significant words and their location within a given column.

index page

A database page containing index rows.

information model

An object-oriented schema that defines metadata constructs used to specify the structure and behavior of an application, process, component, or software artifact.

initial media

The first medium in each media family.

initial snapshot

Files including schema and data, constraints, extended properties, indexes, triggers, and system tables necessary for replication. The initial snapshot is transferred to Subscribers when implementing replication. See also synchronization

instance

A copy of SQL Server running on a computer. A computer can run multiple instances of SQL Server 2000. A computer can run only one instance of SQL Server version 7.0 or earlier, although in some cases it can also be running multiple instances of SQL Server 2000.

integrated security

See Windows authentication

integrity constraint

A property defined on a table that prevents data modifications that would create invalid data.

intent lock

A lock placed on one level of a resource hierarchy to protect shared or exclusive locks on lower-level resources. For example, before a SQL Server 2000 database engine task applies shared or exclusive row locks within a table, it places an intent lock on the table. If another task tries to apply a shared or exclusive lock at the table level, it is blocked by the table-level intent lock held by the first task. The second task does not have to check for individual page or row locks before locking the table ; it only has to check for an intent lock on the table.

interactive structured query language

(ISQL)

An interactive command-prompt utility provided with SQL Server that allows users to execute Transact-SQL statements or batches from a server or workstation and view the results returned.

internal identifier

A more compact form of an object identifier in a repository. An internal identifier is guaranteed to be unique only within a single repository. See also object identifier

International Electrotechnical Commission

(IEC)

One of two international standards bodies responsible for developing international data communications standards. The International Electrotechnical Commission (IEC) works closely with the International Organization for Standardization (ISO) to define standards of computing. They jointly published the ISO/IEC SQL-92 standard for SQL.

International Organization for Standardization

(ISO)

One of two international standards bodies responsible for developing international data communications standards. International Organization for Standardization (ISO) works closely with the International Electrotechnical Commission (IEC) to define standards of computing. They jointly published the ISO/IEC SQL-92 standard for SQL.

Internet-enabled

A publication setting that enables replication to Internet Subscribers.

interprocess communication

(IPC)

A mechanism through which operating system processes and threads exchange data and messages. IPCs include local mechanisms such as Windows shared memory, or network mechanisms such as Windows Sockets.

IPC

See interprocess communication (IPC)

ISO

See International Organization for Standardization (ISO)

ISQL

See interactive structured query language (ISQL)

J

job

A specified series of operations, called steps, performed sequentially by SQL Server Agent.

join

As a verb, to combine the contents of two or more tables and produce a result set that incorporates rows and columns from each table. Tables are typically joined using data that they have in common. As a noun, the process or result of joining tables, as in the term "inner join" to indicate a particular method of joining tables.

join filter

A row filter used in merge replication that defines a relationship between two tables that will be enforced during synchronization, which is similar to specifying a join between two tables.

join operator

A comparison operator in a join condition that determines how the two sides of the condition are evaluated and which rows are returned.

K

kernel

In SQL Server 2000, a subset of the storage engine that is referenced in some error messages. In Windows 2000, the core of the operating system that performs basic operations.

key

A column or group of columns that uniquely identifies a row (PRIMARY KEY), defines the relationship between two tables (FOREIGN KEY), or is used to build an index. See also key column

key column

A column referenced by a primary, foreign, or index key. See also key

keyword

A reserved word in SQL Server that performs a specific function, such as to define, manipulate, and access database objects.

L

latency

The amount of time that elapses when a data change is completed at one server and when that change appears at another (for example, the time between when a change is made at a Publisher and when it appears at the Subscriber).

LCID

See locale identifier (LCID)

leaf

In a tree structure, an element that has no subordinate elements. See also nonleaf

leaf level

The bottom level of a clustered or nonclustered index. In a clustered index, the leaf level contains the actual data pages of the table. In a nonclustered index, the leaf level either points to data pages or points to the clustered index (if one exists), rather than containing the data itself.

linked server

A definition of an OLE DB data source used by SQL Server 2000 distributed queries. The linked server definition specifies the OLE DB provider required to access the data, and includes enough addressing information for the OLE DB provider to connect to the data. Any rowsets exposed by the OLE DB data source can then be referenced as tables, called linked tables, in SQL Server 2000 distributed queries. See also local server

livelock

A request for an exclusive lock that is repeatedly denied because a series of overlapping shared locks keeps interfering. SQL Server detects the situation after four denials and refuses further shared locks. A livelock also occurs when read transactions monopolize a table or page, forcing a write transaction to wait indefinitely. See also deadlock

local Distributor

A server that is configured as both a Publisher and a Distributor for SQL Server replication. See also Distributor, remote Distributor

local group

A group in Windows NT 4.0 or Windows 2000 containing user accounts and global groups from the domain group in which they are created and any trusted domain. Local groups cannot contain other local groups.

local login identification

The identification (ID) a user must use to log in to a local server. A login ID can have up to 128 characters. The characters can be alphanumeric; however, the first character must be a letter (for example, CHRIS or TELLER8).

local server

In SQL Server 2000 connections, an instance of SQL Server 2000 running on the same computer as the application. When resolving references to database objects in a Transact-SQL statement, the instance of SQL Server 2000 executing the statement. In SQL Server 2000 distributed queries, the instance of SQL Server 2000 executing the distributed query. The local server then accesses any linked servers referenced in the query. In SQL Server 2000 remote stored procedures, the instance of SQL Server executing an EXEC statement that references a remote stored procedure. The local server then passes the execution request to the remote server on which the remote stored procedure resides. See also linked server, remote server

local subscription

A subscription to a merge publication using the priority value of the Publisher for conflict detection and resolution.

locale

The Windows operating system attribute that defines certain behaviors related to language. The locale defines the code page, or bit patterns, used to store character data, and the order in which characters are sorted. It also defines language-specific items such as the format used for dates and time and the character used to separate decimals in numbers. Each locale is identified by a unique number, called a locale identifier or LCID. SQL Server 2000 collations are similar to locales in that the collations define language-specific types of behaviors for instances of SQL Server 2000. See also collation, locale identifier (LCID)

locale identifier

(LCID)

A number that identifies a Windows-based locale. See also locale

lock

A restriction on access to a resource in a multiuser environment. SQL Server locks users out of a specific row, column, or file automatically to maintain security or prevent concurrent data modification problems.

lock escalation

The process of converting many fine-grain locks into fewer coarse-grain locks, thereby reducing system overhead.

log file

A file or set of files containing a record of the modifications made in a database. See also data file

logical name

A name used by SQL Server to identify a file. A logical name for a file must correspond to the rules for identifiers and can have as many as 30 characters (for example, ACCOUNTING or LIBRARY).

login

(account)

An identifier that gives a user permission to connect to SQL Server 2000 using SQL Server Authentication. Users connecting to SQL Server 2000 using Windows NT Authentication are identified by their Windows 2000 login, and do not need a separate SQL Server 2000 login.

login security mode

A security mode that determines the manner in which a SQL Server 2000 instance validates a login request. There are two types of login security: Windows authentication and SQL Server authentication.

lookup table

A table, either in a database or hard-coded in the English Query application, that contains codes and the English word or phrase they represent. For example, a gender lookup table contains the following code and English descriptions:
M, Male
F, Female

M

machine DSN

Connection information for a database, stored in the system registry. The connection information consists of parameters and corresponding values that the ODBC Driver Manager uses to establish a connection.

MAPI

See Messaging Application Programming Interface (MAPI)

master database

The database that controls the operation of each instance of SQL Server. It is installed automatically with each instance of SQL Server and keeps track of user accounts, remote user accounts, and remote servers that each instance can interact with. It also tracks ongoing processes, configurable environment variables, system error messages, tapes and disks available on the system, and active locks.

master definition site

See Publisher

master file

The file installed with earlier versions of SQL Server used to store the master, model, and tempdb system databases and transaction logs and the pubs sample database and transaction log.

master site

See Distributor

MDX

See Multidimensional Expressions (MDX)

media description

The text describing the media set. See also media set

media family

All media in a set written by a single device (for example, an initial medium and all continuation media, if any). See also media set

media header

Information about the backup media.

media name

The descriptive name for the entire backup media set.

media set

All media involved in a backup operation. See also media description, media family

merge

The operation that combines two partitions into a single partition.

merge replication

A type of replication that allows sites to make autonomous changes to replicated data, and at a later time, merge changes and resolve conflicts when necessary. See also snapshot replication, transactional replication

message number

A number that identifies a SQL Server 2000 error message.

Messaging Application Programming Interface (MAPI)

An e-mail application programming interface (API).

metadata

Information about the properties of data, such as the type of data in a column (numeric, text, and so on) or the length of a column. It can also be information about the structure of data or information that specifies the design of objects.

method

A function that performs an action by using a COM object, as in SQL-DMO, OLE DB, and ActiveX Data Objects (ADO). See also Component Object Model (COM)

mirroring

The process for protecting against the loss of data because of disk failure by maintaining a fully redundant copy of data on a separate disk. Mirroring can be implemented at several levels: in SQL Server 2000, in the operating system, and in the disk controller hardware.

Mixed Mode

A mode that combines Windows Authentication and SQL Server Authentication. Mixed Mode allows users to connect to an instance of SQL Server, through either a Windows NT 4.0 or Windows 2000 user account or a SQL Server login.

model database

A database installed with SQL Server that provides the template for new user databases. SQL Server 2000 creates a new database by copying in the contents of the model database and then expanding it to the size requested.

Multidimensional Expressions

(MDX)

A syntax used for defining multidimensional objects and querying and manipulating multidimensional data.

multidimensional structure

A database paradigm that treats data not as relational tables and columns, but as information cubes. See also cube

multiple instances

Multiple copies of SQL Server running on the same computer. There can be one default instance, which can be any version of SQL Server. There can be multiple named instances of SQL Server 2000. See also default instance, named instance

multithreaded server application

An application that creates multiple threads within a single process to service multiple user requests at the same time.

multiuser

The ability of a computer to support many users operating at the same time, while providing the computer system's full range of capabilities to each user.

N

named instance

An installation of SQL Server 2000 that is given a name to differentiate it from other named instances and from the default instance on the same computer. A named instance is identified by the computer name and instance name. See also default instance, multiple instances

named pipe

An interprocess communication (IPC) mechanism that SQL Server uses to provide communication between clients and servers. Named pipes permit access to shared network resources.

native format

Bulk copy data files in which the data is stored using the same internal data structures SQL Server uses to store data in SQL Server databases. Bulk copy can quickly process native mode files because it does not have to convert data when transferring it between SQL Server and the bulk copy data file. See also character format

Net-Library

A SQL Server communications component that isolates the SQL Server client software and database engine from the network APIs. The SQL Server client software and database engine send generic network requests to a Net-Library, which translates the request to the specific network commands of the protocol chosen by the user.

nickname

When used with merge replication system tables, a name for another Subscriber that is known to already have a specified generation of updated data. Used to avoid sending an update to a Subscriber that has already received those changes.

niladic functions

Functions that do not have any input parameters. Most niladic SQL Server functions return system information.

nonclustered index

An index in which the logical order of the index is different than the physical, stored order of the rows on disk.

nonleaf

In a tree structure, an element that has one or more subordinate elements. In SQL Server indexes, an intermediate index node that points to other intermediate nodes or leaf nodes. See also leaf

normalization rules

A set of database design rules that minimize data redundancy and results in a database in which the database engine and application software can easily enforce integrity.

NULL

An entry that has no explicitly assigned value. NULL is not equivalent to zero or blank. A value of NULL is not considered to be greater than, less than, or equivalent to any other value, including another value of NULL.

nullability

The attribute of a column, parameter, or variable that specifies whether it allows null data values.

O

object

In databases, one of the components of a database: a table, index, trigger, view, key, constraint, default, rule, user-defined data type, or stored procedure.

object dependencies

References to other objects when the behavior of the first object can be affected by changes in the object it references. For example, if a stored procedure references a table, changes to the table can affect the behavior of the stored procedure.

object identifier

A unique name given to an object. In Meta Data Services, a unique identifier constructed from a globally unique identifier (GUID) and an internal identifier. All objects must have an object identifier. See also internal identifier

object owner

The security account that controls the permissions for an object, usually the creator of the object. Object owner is also called the database object owner.

object permission

An attribute that controls the ability to perform operations on an object. For example, table or view permissions control which users can execute SELECT, INSERT, UPDATE, and DELETE statements against the table or view.

ODBC

See Open Database Connectivity (ODBC)

ODBC data source

The location of a set of data that can be accessed using an ODBC driver. Also, a stored definition that contains all of the connection information an ODBC application requires to connect to the data source. See also data source

ODBC driver

A dynamic-link library (DLL) that an ODBC-enabled application, such as Excel, can use to access an ODBC data source. Each ODBC driver is specific to a database management system (DBMS), such as SQL Server, Access, and so on.

ODS

See Open Data Services (ODS)

OIM

See Open Information Model (OIM)

OLAP

See online analytical processing (OLAP)

OLE DB

A COM-based application programming interface (API) for accessing data. OLE DB supports accessing data stored in any format (databases, spreadsheets, text files, and so on) for which an OLE DB provider is available. See also OLE DB for OLAP

OLE DB for OLAP

Formerly, the separate specification that addressed OLAP extensions to OLE DB. Beginning with OLE DB 2.0, OLAP extensions are incorporated into the OLE DB specification. See also OLE DB

OLE DB provider

A software component that exposes OLE DB interfaces. Each OLE DB provider exposes data from a particular type of data source (for example, SQL Server databases, Access databases, or Excel spreadsheets).

OLTP

See online transaction processing (OLTP)

online analytical processing

(OLAP)

A technology that uses multidimensional structures to provide rapid access to data for analysis. The source data for OLAP is commonly stored in data warehouses in a relational database.

online transaction processing

(OLTP)

A data processing system designed to record all of the business transactions of an organization as they occur. An OLTP system is characterized by many concurrent users actively adding and modifying data.

Open Data Services

(ODS)

The layer of the SQL Server database engine that transfers client requests to the appropriate functions in the database engine. Open Data Services exposes the extended stored procedure API used to write DLL functions that can be called from Transact-SQL statements.

Open Database Connectivity

(ODBC)

A data access application programming interface (API) that supports access to any data source for which an ODBC driver is available. ODBC is aligned with the American National Standards Institute (ANSI) and International Organization for Standardization (ISO) standards for a database Call Level Interface (CLI).

Open Information Model

(OIM)

An information model published by the Meta Data Coalition (MDC) and widely supported by software vendors. The OIM is a formal description of metadata constructs organized by subject area.

optimize synchronization

An option in merge replication that allows you to minimize network traffic when determining whether recent changes have caused a row to move into or out of a partition that is published to a Subscriber.

optimizer

See query optimizer

P

page

In a virtual storage system, a fixed-length block of contiguous virtual addresses copied as a unit from memory to disk and back during paging operations. SQL Server allocates database space in pages. In SQL Server, a page is 8 kilobytes (KB) in size.

page split

The process of moving half the rows or entries in a full data or index page to two new pages to make room for a new row or index entry.

partitioning

The process of replacing a table with multiple smaller tables. Each smaller table has the same format as the original table, but with a subset of the data. Each partitioned table has rows allocated to it based on some characteristic of the data, such as specific key ranges. The rules that define into which table the rows go must be unambiguous. For example, a table is partitioned into two tables. All rows with primary key values lower than a specified value are allocated to one table, and all keys equal to or greater than the value are allocated to the other. Partitioning can improve application processing speeds and reduce the potential for conflicts in multisite update replication. You can improve the usability of partitioned tables by creating a view. The view, created by a union of select operations on all the partitioned tables, presents the data as if it all resided in a single table. See also filtering, vertical partitioning, horizontal partitioning

permissions

Authorization that enforces database security. SQL Server permissions specify the Transact-SQL statements, views, and stored procedures each user is authorized to use. There are two types of permissions: object permissions and statement permissions.

physical name

The path where a file or mirrored file is located. The default is the path of the Master.dat file followed by the first eight characters of the file's logical name. For example, if Accounting is the logical name, and the Master.dat file is located in Sql\Data, the default physical name is Sql\Data\Accounti.dat. For a mirrored file, the default is the path of the Master.mir file followed by the first eight characters of the mirror file's logical name. For example, if Maccount is the name of the mirrored file, and the Master.mir file is located in Sql\Data, the default physical name is Sql\Data\Maccount.mir.

physical reads

A request for a database page in which SQL Server must transfer the requested page from disk to the SQL Server buffer pool. All attempts to read pages are called logical reads. If the page is already in the buffer, there is no associated physical read generated by the logical read. The number of physical reads never exceeds the number of logical reads. In a well-tuned instance of SQL Server, the number of logical reads is typically much higher than the number of physical reads.

PK

See primary key (PK)

primary key

(PK)

A column or set of columns that uniquely identifies all the rows in a table. Primary keys do not allow null values. No two rows can have the same primary key value; therefore, a primary key value always uniquely identifies a single row. More than one key can uniquely identify rows in a table, and each of these keys is called a candidate key. Only one candidate can be chosen as the primary key of a table ; all other candidate keys are known as alternate keys. Although tables are not required to have primary keys, it is good practice to define them. In a normalized table, all of the data values in each row are fully dependent on the primary key. For example, in a normalized employee table that has EmployeeID as the primary key, all of the columns should contain data related to a specific employee. The table does not have the column DepartmentName because the name of the department is dependent on a department ID, not on an employee ID.

primary table

The "one" side of two related tables in a one-to-many relationship. A primary table should have a primary key and each record should be unique. An example of a primary table is a table of customer names that are uniquely identified by a CustomerID primary key field.

procedure cache

The part of the SQL Server memory pool that is used to store execution plans for Transact-SQL batches, stored procedures, and triggers. Execution plans record the steps that SQL Server must take to produce the results specified by the Transact-SQL statements contained in the batches, stored procedures, or triggers.

producer

A SQL Profiler process that collects events in a specific event category and sends the data to a SQL Server Profiler queue.

property

A named attribute of a control, field, or database object that you set to define one of the object s characteristics (such as size, color, or screen location) or an aspect of its behavior (such as whether it is hidden).

property pages

A tabbed dialog box in which you can identify the characteristics of tables, relationships, indexes, constraints, and keys. Every object in a database diagram has a set of properties that determine the definition of a database object. Each set of tabs shows only the properties specific to the selected object. If multiple objects are selected, the property pages show the properties of the first object you selected.

provider

An OLE DB provider. An in-process dynamic-link library (DLL) that provides access to a database.

publication

A publication is a collection of one or more articles from one database. This grouping of multiple articles makes it easier to specify a logically related set of data and database objects that you want to replicate at the same time.

publication database

A database on the Publisher from which data and database objects are marked for replication as part of a publication that is propagated to Subscribers.

publication retention period

A predetermined length of time that regulates how long subscriptions will receive updates during synchronizations and remain activated in databases.

published data

Data at the Publisher that has been replicated.

Publisher

A server that makes data available for replication to other servers, detects changed data, and maintains information about all publications at the site.

publishing table

The table at the Publisher in which data has been marked for replication and is part of a publication.

pubs database

A sample database provided with SQL Server.

pull subscription

A subscription created and administered at the Subscriber. Information about the publication and the Subscriber is stored. See also push subscription

push subscription

A subscription created and administered at the Publisher. Information about the publication and Subscriber is stored. See also pull subscription

Q

query optimizer

The SQL Server database engine component responsible for generating efficient execution plans for SQL statements.

queue

A SQL Server Profiler queue provides a temporary holding place for server events to be captured.

R

RDBMS

See relational database management system (RDBMS)

record

A group of related fields (columns) of information treated as a unit. A record is more commonly called a row in a SQL database.

recovery

An operation in which SQL Server is restarted after a system failure; the transaction log is used to roll forward all committed transactions and roll back all uncommitted transactions in order to bring the database to the state it was in at the point of failure.

recovery interval

The maximum amount of time that the database engine should require to recover a database. The database engine ensures that the active portion of the database log is small enough to recover the database in the amount of time specified for the recovery interval.

referenced key

A primary key or unique key referenced by a foreign key.

referencing key

See foreign key (FK)

referential integrity

(RI)

A state in which all foreign key values in a database are valid. For a foreign key to be valid, it must contain either the value NULL, or an existing key value from the primary or unique key columns referenced by the foreign key.

reflexive relationship

A relationship from a column or combination of columns in a table to other columns in that same table. A reflexive relationship is used to compare rows within the same table. In queries, this is called a self- join.

relational database

A collection of information organized in tables. Each table models a class of objects of interest to the organization (for example, Customers, Parts, Suppliers). Each column in a table models an attribute of the object (for example, LastName, Price, Color). Each row in a table represents one entity in the class of objects modeled by the table (for example, the customer name John Smith or the part number 1346). Queries can use data from one table to find related data in other tables.

relational database management system

(RDBMS)

A system that organizes data into related rows and columns. SQL Server is a relational database management system (RDBMS).

remote data

Data stored in an OLE DB data source that is separate from the current instance of SQL Server. The data is accessed by establishing a linked server definition or using an ad hoc connector name.

remote Distributor

A server for SQL Server replication configured as a Distributor that is separate from the server configured as the Publisher. See also Distributor, local Distributor

remote login identification

The login identification (login ID) assigned to a user for accessing remote procedures on a remote server.

remote server

A definition of an instance of SQL Server used by remote stored procedure calls. Remote servers are still supported in SQL Server 2000, but linked servers offer greater functionality. See also local server

remote stored procedure

A stored procedure located on one instance of SQL Server that is executed by a statement on another instance of SQL Server. In SQL Server 2000, remote stored procedures are supported, but distributed queries offer greater functionality.

remote table

A table stored in an OLE DB data source that is separate from the current instance of SQL Server. The table is accessed by either establishing a linked server definition or using an ad hoc connector name.

replicated data

Data at the Subscriber that has been received from a Publisher.

replication

A process that copies and distributes data and database objects from one database to another and then synchronizes information between databases for consistency.

Replication Conflict Viewer

Allows users to view and resolve conflicts that occurred during the merge replication process and to review the manner in which conflicts have been resolved.

Replication Monitor

Allows users to view and manage replication agents responsible for various replication tasks and to troubleshoot potential problems at the Distributor.

replication scripting

The generation of .sql scripts that can be used to configure and disable replication.

replication topology

A network layout that defines the relationship between servers and the copies of data and clarifies the logic that determines how data flows between servers.

repository

A database containing information models that, in conjunction with the executable software, manage the database. The term can also refer to an installation of Meta Data Services.

repository engine

Object-oriented software that provides management support for and customer access to a repository database.

repository object

A COM object that represents a data construct stored in a repository type library.

Repository SQL schema

A set of standard tables used by the repository engine to manage all repository objects, relationships, and collections. Repository SQL schema maps information model elements to SQL schema elements.

Repository Type Information Model

(RTIM)

A core object model that represents repository type definitions for Meta Data Services. This object model is composed of abstract classes upon which instances of information models are based.

republish

For a Subscriber to publish data received from a Publisher to another Subscriber.

republisher

A Subscriber that publishes data that it has received from a Publisher.

resolution strategy

A set of criteria that the repository engine evaluates sequentially when selecting an object, where multiple versions exist and version information is unspecified in the calling program.

restore

An operation in which a SQL Server backup file is copied back into the SQL Server database. This operation takes the database back to the state it was in when the backup was created.

result set

The set of rows returned from a SELECT statement. The format of the rows in the result set is defined by the column-list of the SELECT statement.

revoke

To remove a previously granted or denied permission from a user account, role, or group in the current database.

RI

See referential integrity (RI)

role

A SQL Server security account that is a collection of other security accounts that can be treated as a single unit when managing permissions. A role can contain SQL Server logins, other roles, and Windows logins or groups.

roll back

To remove the updates performed by one or more partially completed transactions. Rollbacks are required to restore the integrity of a database after an application, database, or system failure. See also commit

roll forward

To apply all the completed transactions from a database or log backup in order to recover a database to a point in time or the point of failure (for example, after events such as the loss of a disk).

row

In a SQL table, the collection of elements that form a horizontal line in the table. Each row in the table represents a single occurrence of the object modeled by the table and stores the values for all the attributes of that object. For example, in the Northwind sample database, the Employees table models the employees of the Northwind Traders Company. The first row in the table records all the information (for example, name and title) about the employee who has employee ID 1. See also column

row filter

A filter that specifies a subset of rows from a table to be published and when specific rows need to be propagated to Subscribers.

row lock

A lock on a single row in a table.

rowset

The OLE DB object used to contain a result set. It also exhibits cursor behavior depending on the rowset properties set by an application.

RTIM

See Repository Type Information Model (RTIM)

rule

A database object that is bound to columns or user-defined data types, and specifies which data values are acceptable in a column. CHECK constraints provide the same functionality and are preferred because they are in the SQL-92 standard.

S

savepoint

A marker that allows an application to roll back part of a transaction if a minor error is encountered. The application must still commit or roll back the full transaction when it is complete.

scheduled backup

An automatic backup accomplished by SQL Server Agent when defined and scheduled as a job.

schema

In the SQL-92 standard, a collection of database objects that are owned by a single user and form a single namespace. A namespace is a set of objects that cannot have duplicate names. For example, two tables can have the same name only if they are in separate schemas; no two tables in the same schema can have the same name. In Transact-SQL, much of the functionality associated with schemas is implemented by database user IDs. In database tools, schema also refers to the catalog information that describes the objects in a schema or database.

schema rowset

A special OLE DB or Analysis Services rowset that reports catalog information for objects in databases or multidimensional cubes. For example, the OLE DB schema rowset DBSCHEMA_COLUMNS describes columns in tables.

script

A collection of Transact-SQL statements used to perform an operation. Transact-SQL scripts are stored as files, usually with the .sql extension.

search condition

In a WHERE or HAVING clause, predicates that specify the conditions that the source rows must meet to be included in the SQL statement. For example, the statement SELECT * FROM Employees WHERE Title = Sales Representative returns only those rows that match the search condition: Title = Sales Representative .

Security Identifier

(SID)

A unique value that identifies a user who is logged on to the security system. SIDs can identify either one user or a group of users.

SELECT

The Transact-SQL statement used to return data to an application or another Transact-SQL statement, or to populate a cursor. The SELECT statement returns a tabular result set consisting of data that is typically extracted from one or more tables. The result set contains only data from rows that match the search conditions specified in WHERE or HAVING clauses.

select list

The SELECT statement clause that defines the columns of the result set returned by the statement. The select list is a comma-separated list of expressions, such as column names, functions, or constants.

server cursor

A cursor implemented on the server. The cursor itself is built at the server, and only the rows fetched by an application are sent to the client. See also API server cursor

server name

A name that uniquely identifies a server computer on a network. SQL Server applications can connect to a default instance of SQL Server by specifying only the server name. SQL Server applications must specify both the server name and instance name when connecting to a named instance on a server.

Setup initialization file

A text file, using the Windows .ini file format, that stores configuration information allowing SQL Server to be installed without a user having to be present to respond to prompts from the Setup program.

severity level

A number indicating the relative significance of an error generated by the SQL Server database engine. Values range from informational (1) to severe (25).

shared lock

A lock created by nonupdate (read) operations. Other users can read the data concurrently, but no transaction can acquire an exclusive lock on the data until all the shared locks have been released.

showplan

A report showing the execution plan for a SQL statement. SET SHOWPLAN_TEXT and SET SHOWPLAN_ALL produce textual showplan output. SQL Query Analyzer and SQL Server Enterprise Manager can display showplan information as a graphical tree.

SID

See Security Identifier (SID)

single-user mode

A state in which only one user can access a resource. Both SQL Server instances and individual databases can be put into single-user mode.

Snapshot Agent

A SQL Server Agent job that prepares snapshot files containing schema and data of published tables, stores the files in the snapshot folder, and inserts synchronization jobs in the publication database.

Snapshot Agent utility

A utility that configures and triggers the Snapshot Agent, which prepares snapshot files containing schema and data of published tables and database objects.

snapshot replication

A type of replication that distributes data exactly as it appears at a specific moment in time and does not monitor for modifications made to the data. See also merge replication, transactional replication

sort order

The set of rules in a collation that define how characters are evaluated in comparison operations and the sequence in which they are sorted.

source and target

A browsing technique in which a source object is used to retrieve its target object or objects through their relationship.

source database

See publication database

SQL

See Structured Query Language (SQL)

SQL collation

A set of SQL Server 2000 collations whose characteristics match those of commonly used code page and sort order combinations from earlier versions of SQL Server. SQL collations are compatibility features that let sites choose collations that match the behavior of their earlier systems. See also collation

SQL database

A database based on Structured Query Language (SQL).

SQL expression

Any combination of operators, constants, literal values, functions, and names of tables and fields that evaluates to a single value. For example, use expressions to define calculated fields in queries.

SQL Mail

A component of SQL Server that allows SQL Server to send and receive mail messages through the built-in Windows NT 4.0 or Windows 2000 Messaging Application Programming Interface (MAPI). A mail message can consist of short text strings, the output from a query, or an attached file.

SQL Profiler

A SQL Server utility that is used to monitor server performance and activity. SQL Profiler is used for tracking events within SQL Server.

SQL query

A SQL statement such as SELECT, INSERT, UPDATE, DELETE, or CREATE TABLE.

SQL Query Analyzer

SQL Query is a graphical user interface for designing and testing Transact-SQL statements, batches, and scripts interactively.

SQL Server Agent

A Windows service that performs background tasks, such as scheduling SQL Server jobs and notifying the appropriate person of problems within SQL Server.

SQL Server authentication

One of two mechanisms for validating attempts to connect to instances of SQL Server. Users must specify a SQL Server login ID and password when they connect. The SQL Server instance ensures that the login ID and password combination are valid before allowing the connection to succeed. Windows authentication is the preferred authentication mechanism. See also authentication, Windows authentication

SQL Server Event Forwarding Server

A central instance of SQL Server that manages SQL Server Agent events forwarded to it by other instances. Enables central management of SQL Server events.

SQL Server login

An account stored in SQL Server that allows users to connect to SQL Server.

SQL Server role

See role

SQL Server user

See user (account)

SQL statement

A SQL or Transact-SQL command, such as SELECT or DELETE, that performs some action on data.

SQL-92

The version of the SQL standard published in 1992. The international standard is ISO/IEC 9075:1992 Database Language SQL. The American National Standards Institute (ANSI) also published a corresponding standard (Data Language SQL X3.135-1192), so SQL-92 is sometimes referred to as ANSI SQL in the United States.

standard security

See definition for: SQL Server authentication

statement permission

An attribute that controls whether a user can execute CREATE or BACKUP statements.

step object

A Data Transformation Services (DTS) object that coordinates the flow of control and execution of tasks in a DTS package. A task that does not have an associated step object is never executed.

store-and-forward database

See distribution database

stored procedure

A precompiled collection of Transact-SQL statements stored under a name and processed as a unit. SQL Server supplies stored procedures for managing SQL Server and displaying information about databases and users. SQL Server-supplied stored procedures are called system stored procedures.

string

A set of contiguous bytes that contain a single character-based or binary data value. In character strings, each byte, or pair of bytes, represents a single alphabetic letter, special character, or number. In binary strings, the entire value is considered to be a single stream of bits that do not have any inherent pattern. For example, the constant 'I am 32.' is an 8-byte character string, whereas the constant 0x0205efa3 is a 4-byte binary string.

Structured Query Language

(SQL)

A language used to insert, retrieve, modify, and delete data in a relational database. SQL also contains statements for defining and administering the objects in a database. SQL is the language supported by most relational databases, and is the subject of standards published by the International Standards Organization (ISO) and the American National Standards Institute (ANSI). SQL Server 2000 uses a version of the SQL language called Transact-SQL.

structured storage file

See COM-structured storage file

subscribe

To request data from a Publisher.

Subscriber

A server that receives copies of published data.

subscription

An order that defines what data will be published, when, and to what Subscriber.

subscription database

A database at the Subscriber that receives data and database objects published by a Publisher.

synchronization

In replication, the process of maintaining the same schema and data at a Publisher and at a Subscriber. See also initial snapshot

system administrator

The person or group of people responsible for managing an instance of SQL Server. System administrators have full permissions to perform all actions in an instance of SQL Server. System administrators either are members of the sysadmin fixed server role, or log in using the sa login ID.

system catalog

A set of system tables that describe all the features of an instance of SQL Server. The system catalog records metadata such as the definitions of all users, all databases, all objects in each database, and system configuration information such as server and database option settings. See also database catalog

system databases

A set of four databases present in all instances of SQL Server that are used to store system information:
The master database stores all instance-level metadata, and records the location of all other databases.
The tempdb database stores transient objects that exist only for the length of a single statement or connection, such as worktables and temporary tables or stored procedures.
The model database is used as a template for creating all user databases.
The msdb database is used by the SQL Server Agent to record information on jobs, alerts, and backup histories.
See also user database

system functions

A set of built-in functions that perform operations on and return the information about values, objects, and settings in SQL Server.

system stored procedures

A set of SQL Server-supplied stored procedures that can be used for actions such as retrieving information from the system catalog or performing administration tasks.

system tables

Built-in tables that form the system catalog for SQL Server. System tables store all the metadata for an instance of SQL Server, including configuration information and definitions of all the databases and database objects in the instance. Users should not directly modify any system table.

T

table

A two-dimensional object, consisting of rows and columns, used to store data in a relational database. Each table stores information about one of the types of objects modeled by the database. For example, an education database would have one table for teachers, a second for students, and a third for classes.
The columns of a table represent an attribute of the modeled object (for example, first name, last name, and address). Each row represents one occurrence of the modeled object. For example, one row in the Class table would record the information about an Algebra 1 class taught at 9:00 A.M. and another would record the information about a World History class taught at 10:00 A.M.

table lock

A lock on a table including all data and indexes.

table scan

A data retrieval operation in which the database engine must read all the pages in a table to find the rows that qualify for a query.

table-level constraint

Constraints that allow various forms of data integrity to be defined on one column (column-level constraint) or several columns (table-level constraints) when the table is defined or altered. Constraints support domain integrity, entity integrity, and referential integrity, as well as user-defined integrity.

tabular data stream

(TDS)

The SQL Server internal client/server data transfer protocol. TDS allows client and server products to communicate regardless of operating system platform, server release, or network transport.

tape backup

A backup operation to any tape device supported by Windows NT 4.0 and Windows 2000. If you are creating a tape backup file, you must first install the tape device by using Windows NT 4.0 and Windows 2000. The tape device must be physically attached to the SQL Server computer that you are backing up.

target object

See source and target

task

See job

task object

A Data Transformation Services (DTS) object that defines pieces of work to be performed as part of the data transformation process. For example, a task can execute a SQL statement or move and transform heterogeneous data from an OLE DB source to an OLE DB destination using the DTS Data Pump.

TDS

See tabular data stream (TDS)

tempdb database

The database that provides a storage area for temporary tables, temporary stored procedures, and other temporary working storage needs.

thread

An operating system component that allows the logic of multiuser applications to be performed as several separate, asynchronous execution paths. The SQL Server relational database engine executes multiple threads in order to make use of multiple processors. The use of threads also helps ensure that work is being performed for some user connections even when other connections are blocked (for example, when waiting for a disk read or write operation to complete).

tool

A SQL Server application with a graphical user interface used to perform common tasks.

trace file

A file used by SQL Profiler to record monitored events.

Transact-SQL

The language containing the commands used to administer instances of SQL Server, create and manage all objects in an instance of SQL Server, and to insert, retrieve, modify, and delete all data in SQL Server tables. Transact-SQL is an extension of the language defined in the SQL standards published by the International Standards Organization (ISO) and the American National Standards Institute (ANSI).

Transact-SQL cursor

A server cursor defined by using the Transact-SQL DECLARE CURSOR syntax. Transact-SQL cursors are intended for use in Transact-SQL batches, stored procedures, and triggers.

transaction

A group of database operations combined into a logical unit of work that is either wholly committed or rolled back. A transaction is atomic, consistent, isolated, and durable.

transaction log

A database file in which all changes to the database are recorded. It is used by SQL Server during automatic recovery.

transaction processing

Data processing used to efficiently record business activities, called transactions, that are of interest to an organization (for example, sales, orders for supplies, or money transfers). Typically, online transaction processing (OLTP) systems perform large numbers of relatively small transactions.

transaction rollback

Rollback of a user-specified transaction to the last savepoint inside a transaction or to the beginning of a transaction.

transactional replication

A type of replication in which an initial snapshot of data is applied at Subscribers, and then when data modifications are made at the Publisher, the individual transactions are captured and propagated to Subscribers. See also merge replication, snapshot replication

transformable subscription

A subscription that allows data movement, transformation mapping, and filtering capabilities of Data Transformation Services (DTS) during replication.

transformation

In data warehousing, the process of changing data extracted from source data systems into arrangements and formats consistent with the schema of the data warehouse.

trigger

A stored procedure that executes when data in a specified table is modified. Triggers are often created to enforce referential integrity or consistency among logically related data in different tables.

trusted connection

A Windows network connection that can be opened only by users who have been authenticated by the network. The users are identified by their Windows login ID and do not have to enter a separate SQL Server login ID. See also Windows authentication

two-phase commit

A process that ensures transactions that apply to more than one server are completed on all servers or on none.

U

Unicode

Unicode defines a set of letters, numbers, and symbols that SQL Server recognizes in the nchar, nvarchar, and ntext data types. It is related to but separate from character sets. Unicode has more than 65,000 possible values compared to a character set s 256, and takes twice as much space to store. Unicode includes characters for most languages.

Unicode collation

A set of rules that determine how SQL Server compares, collates, and presents Unicode data in response to database queries. It acts as a sort order for Unicode data.

Unicode format

Data stored in a bulk copy data file using Unicode characters.

update

To modify one or more data values in an existing row or rows, typically by using the UPDATE statement. Sometimes, the term update refers to any data modification, including INSERT, UPDATE, and DELETE operations.

update lock

A lock placed on resources (such as row, page, table ) that can be updated. Updated locks are used to prevent a common form of deadlock that occurs when multiple sessions are locking resources and are potentially updating them later.

update query

A query that changes the values in columns of one or more rows in a table.

update statistics

A process that recalculates information about the distribution of key values in specified indexes. These statistics are used by the query optimizer to determine the most efficient way to execute a query.

user

(account)

A SQL Server security account or identifier that represents a specific user in a database. Each user's Windows account or SQL Server login is mapped to a user account in a database. Then the appropriate permissions are granted to the user account. Each user account can only access data with which it has been granted permission to work.

user database

A database created by a SQL Server user and used to store application data. Most users connecting to instances of SQL Server reference user databases only, not system databases. See also system databases

user-defined data type

A data type, based on a SQL Server data type, created by the user for custom data storage. Rules and defaults can be bound to user-defined data types (but not to system data types). See also base data type

user-defined event

A type of message, defined by a user, that can be traced by SQL Profiler or used to fire a custom alert. Typically, the user is the system administrator.

user-defined function

In SQL Server, a Transact-SQL function defined by a user. Functions encapsulate frequently performed logic in a named entity that can be called by Transact-SQL statements instead of recoding the logic in each statement.

utility

A SQL Server application run from a command prompt to perform common tasks.

V

vertical filtering

Filtering columns from a table. When used as part of replication, the table article created contains only selected columns from the publishing table. See also filtering, vertical partitioning

vertical partitioning

Segmenting a single table into multiple tables based on selected columns. Each of the multiple tables has the same number of rows but fewer columns. See also partitioning, vertical filtering

view

A database object that can be referenced the same way as a table in SQL statements. Views are defined using a SELECT statement and are analogous to an object that contains the result set of this statement.

W

WHERE clause

The part of a SQL statement that specifies which records to retrieve.

Windows authentication

One of two mechanisms for validating attempts to connect to instances of SQL Server. Users are identified by their Windows user or group when they connect. Windows authentication is the most secure mechanism for connecting to SQL Server. See also SQL Server authentication, trusted connection

Windows collation

A set of rules that determine how SQL Server sorts character data. It is specified by name in the Windows Control Panel and in SQL Server 2000 during Setup.

write-ahead log

A transaction logging method in which the log is always written prior to the data.