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sample data
Artificially generated data presented instead of actual data when a cube is queried before it has been processed. Sample data enables you to view the effects of structure changes while modifying a cube.
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.
scalar aggregate
An aggregate function, such as MIN(), MAX(), or AVG(), that is specified in a SELECT statement column list that contains only aggregate functions. When the column list contains only aggregate functions, then the result set has only one row giving the aggregate values calculated from the source rows that match the WHERE clause predicates.
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, database user IDs implement much of the functionalities associated with schemas. In database tools, schema also refers to the catalog information that describes the objects in a schema or database. In Analysis Services, a schema is a description of multidimensional objects (such as cubes and dimensions).
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, and the Analysis Services MDSCHEMA_MEASURES schema rowset describes the measures in a cube.
script
A collection of Transact-SQL statements used to perform an operation. Transact-SQL scripts are stored as files (usually with the .SQL extension).
scroll
The capability to move around a cursor in directions other than forward-only. Users can move up and down the cursor.
security
A system to authenticate a user’s identity and grant or deny access to different database objects. In SQL Server 2000, there are two types of authentication modes: Windows Authentication Mode and Mixed Mode. Security on objects can be granted on most objects, including columns within a table.
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.
segmentation
A data mining technique that analyzes data to discover mutually exclusive collections of records that share similar attribute sets. A segmentation algorithm can use unsupervised learning techniques such as clustering or supervised learning for a specific prediction field. See also clustering.
SELECT
The Transact-SQL statement used to return data to an application or to 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. In Analysis Services, SELECT is the multidimensional expressions (MDX) statement used to query cubes and return recordsets of multidimensional data.
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.
SELECT query
A query that returns rows into a result set from one or more tables. A SELECT query can contain specifications for those columns to return, the rows to select, the order to put the rows in, and how to group (summarize) information.
self-join
A join in which records from a table are combined with other records from the same table when there are matching values in the joined fields. A self-join can be an inner join or an outer join. In database diagrams, a self-join is called a reflexive relationship.
semantic object
An object that can be represented by a database object or by another real-world object. For example, an entity and a relationship are semantic objects.
semi-additive measure
A measure that can be summed along one or more (but not all) dimensions in a cube. For example, a quantity-on-hand measure of inventory can be summed along the geography dimension to produce a total quantity on hand for all warehouses, but it cannot be summed along the time dimension because the measure specifies snapshot quantities periodically in time.
sensitive cursor
A cursor that can reflect data modifications made to underlying data by other users while the cursor is open. Updates, deletes, and inserts made by other users are reflected in the sensitive cursor. Sensitive cursors are typically used in Transact-SQL batches, stored procedures, and triggers by omitting the INSENSITIVE keyword on the DECLARE_CURSOR statement.
sequence
See identity column.
sequenced collection
A collection of destination objects of a sequenced relationship object. See also sequenced relationship.
sequenced relationship
A relationship in a repository that specifies explicit positions for each destination object within the collection of destination objects. See also origin object, relationship object, sequenced collection.
serializable
The highest transaction isolation level. Serializable transactions lock all rows that they read or modify to ensure that the transaction is completely isolated from other tasks. This procedure guarantees that a series of serializable transactions will always produce the same results if run in the same sequence.
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 the instance name when connecting to a named instance on a server.
session
In English Query, a sequence of operations performed by the English Query engine. A session begins when a user logs on and ends when the user logs off. All operations during a session form one transaction scope and are subject to permissions determined by the login username and password.
Setup initialization file
A text file that uses the Windows .INI file format to store configuration information, enabling 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 dimension
A dimension created within a database that can be used by any cube in the database. See also private dimension.
shared lock
A lock created by non-update (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. Query Analyzer and 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.
slice
A subset of the data in a cube, specified by limiting one or more dimensions by members of the dimension. For example, facts for a particular year constitute a slice of multi-year data. See also axis.
smalldatetime data type
Date and time data from January 1, 1900 through June 6, 2079 with an accuracy of one minute.
smallint data type
SQL Server system integer data from –2^15 (–32,768) through 2^15 – 1 (32,767).
smallmoney data type
A SQL Server system data type that stores monetary values from –214,748.3648 through +214,748.3647, with accuracy to a ten-thousandth of a monetary unit. The storage size is four bytes. When smallmoney values are displayed, they are rounded up two places.
Snapshot Agent
Prepares snapshot files containing the schema and data of published tables, stores the files in the snapshot folder, and inserts synchronization jobs in the publication database.
Snapshot Agent utility
Configures and triggers the Snapshot Agent, which prepares snapshot files containing schema and data of published tables and database objects.
snapshot cursor
See static cursor.
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.
snowflake schema
An extension of a star schema such that one or more dimensions are defined by multiple tables. In a snowflake schema, only primary dimension tables are joined to the fact table. Additional dimension tables are joined to primary dimension tables. See also primary dimension table, star schema.
solve order
The order of evaluation (from the highest to the lowest solve order) and calculation (from the lowest to the highest solve order) for calculated members, custom members, custom rollup formulas, and calculated cells in a single calculation pass of a multidimensional cube. Solve order is used to determine formula precedence when calculating values for cells in multidimensional cubes, but only within a single calculation pass. See also calculation condition, calculation formula, calculation pass, calculation subcube, pass order.
sort order
The set of rules in a collation that defines 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 cube
The cube on which a linked cube is based. See also linked cube.
source database
In data warehousing, the database from which data is extracted for use in the data warehouse. See also publication database.
source object
The single object to which all objects in a particular collection are connected by way of relationships that are all of the same relationship type. For destination collections, the source object is the destination object. For origin collections, the source object is the origin object.
source partition
An Analysis Services partition that is merged into another and is deleted automatically at the end of the merger process. See also target partition.
sparsity
The relative percentage of a multidimensional structure’s cells that do not contain data. Analysis Services stores only cells that contain data. A sparse cube requires less storage than a dense cube of identical structure design. See also data explosion, density.
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 enable sites to 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.
SQL Mail
A component of SQL Server that allows SQL Server to send and receive mail messages through the built-in Windows NT 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 query
A SQL statement, such as SELECT, INSERT, UPDATE, DELETE, or CREATE_TABLE.
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. This server 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.
sql_variant data type
A data type that stores values of various SQL Server-supported data types except text, ntext, timestamp, and sql_variant.
standard security
See SQL Server Authentication.
star join
A join between a fact table (typically a large fact table) and at least two dimension tables. The fact table is joined with each dimension table on a dimension key. SQL Server considers special index manipulation strategies on these queries to minimize access to the fact table. An example of a schema that participates in a star join query could be a sales table, the fact table (containing millions of rows), a product table, (containing the description of several hundred products), and a store table (containing several dozen store names). In this example, the product and store tables are dimension tables. A query for selecting sales data for a small set of stores and a subset of products that are restricted by attributes not present in the sales database is an ideal candidate for the star query optimization. See also fact table.
star schema
A relational database structure in which data is maintained in a single fact table at the center of the schema with additional dimension data stored in dimension tables. Each dimension table is directly related to and usually joined to the fact table by a key column. Star schemas are used in data warehouses. See also denormalize, fact table, snowflake schema.
statement permission
An attribute that controls whether a user can execute CREATE or BACKUP statements.
static cursor
A cursor that shows the result set exactly as it was at the time the cursor was opened. Static cursors do not reflect updates, deletes, or inserts that are made to underlying data while the cursor is open. They are sometimes called snapshot cursors.
static SQL statements
In Embedded SQL for C, a SQL statement that is built at the time the application is compiled. The statement is created as a stored procedure when the application is compiled, and the stored procedure is executed when the application is run.
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 that are stored under a name and are processed as a unit. SQL Server supplies stored procedures for managing SQL Server and for displaying information about databases and users. SQL Server–supplied stored procedures are called system stored procedures.
string
A set of contiguous bytes that contains a single, character-based or binary data value. In character strings, each byte (or pair of bytes) represents a single alphabetic letter, a special character, or a number. In binary strings, the entire value is considered to be a single stream of bits that does not have any inherent pattern. For example, the constant “I am 32.” is an eight-byte character string, while the constant 0x0205efa3 is a four- byte binary string.
string functions
Functions that perform operations on character or binary strings. Built-in string functions return values commonly needed for operations on character data.
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 Organization for Standardization (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.
subquery
A SELECT statement nested inside another SELECT, INSERT, UPDATE, or DELETE statement or inside another subquery.
subscribe
To request data from a Publisher.
Subscriber
A server that receives copies of published data.
subscribing server
An Analysis server that stores a linked cube. See also publishing server, linked cube.
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.
subset
A selection of tables and the relationship lines between them that is part of a larger database diagram. This selection can be copied to a new database diagram (called subsetting the diagram).
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 (sa)
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 are either members of the sysadmin fixed server role or log in by 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 only exist 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 about 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 administrative 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.
