Glossary

access descriptor

a SAS/ACCESS file that describes data that is managed by SAS, by a database management system, or by a PC-based software application such as Microsoft Excel, Lotus 1-2-3, or dBASE. After creating an access descriptor, you can use it as the basis for creating one or more view descriptors. See also view descriptor.

appliance

See data warehouse appliance.

bulk load

to load large amounts of data into a database object, using methods that are specific to a particular DBMS. Bulk loading enables you to rapidly and efficiently add multiple rows of data to a table as a single unit.

client

an application that requests either resources or services from a server, possibly over a network.

column

a vertical component of a table. Each column has a unique name, contains data of a specific type, and has particular attributes. A column is analogous to a variable in SAS terminology.

column function

an operation that is performed for each value in the column that is named as an argument of the function. For example, AVG(SALARY) is a column function.

commit

the process that ends a transaction and that makes permanent any changes to the database that the user made during the transaction. See also rollback.

data entity (entity)

an Rdb or VMS item that can be defined and manipulated using VAX SQL. Rdb and VMS entities include databases, tables, views, columns, and indexes.

data set

See SAS data set.

DATA step view

a type of SAS data set that consists of a stored DATA step program. A DATA step view contains a definition of data that is stored elsewhere; the view does not contain the physical data. The view's input data can come from one or more sources, including external files and other SAS data sets. Because a DATA step view only reads (opens for input) other files, you cannot update the view's underlying data.

data type (type)

an attribute of every column in a table or database, indicating the type of data in the column and how much physical storage it occupies.

data value

a unit of character, numeric, or alphanumeric information that is stored as a single item in a data record.

data view

See SAS data view.

data warehouse appliance (appliance)

an integrated set of servers, storage, one or more operating systems, DBMS, and software that is specifically pre-installed and pre-optimized for data warehousing.

database

an organized collection of related data. A database usually contains named files, named objects, or other named entities such as tables, views, and indexes.

database management system (DBMS)

a software application that enables you to create and manipulate data that is stored in the form of databases. See also relational database management system.

DBMS

See database management system.

engine (SAS engine)

a component of SAS software that reads from or writes to a file. Various engines enable SAS to access different types of file formats.

entity

See data entity.

explicit pass-through

a form of the SQL pass-through facility that passes the user-written, DBMS-specific SQL query code directly to a particular DBMS for processing. See also implicit pass-through.

foreign key

a column or combination of columns in one table that references the corresponding primary key in another table. A foreign key must have the same attributes as the primary key that it references.

function

See SAS function.

Hadoop Distributed File System (HDFS)

a portable, scalable framework, written in Java, for managing large files as blocks of equal size. The files are replicated across multiple host machines in a Hadoop cluster in order to provide fault tolerance.

HDFS

See Hadoop Distributed File System.

implicit pass-through

a form of the SQL pass-through facility that translates SAS SQL query code to the DBMS-specific SQL code, enabling the translated code to be passed to a particular DBMS for processing. See also explicit pass-through.

index

See SAS index.

informat

See SAS informat.

interactive line mode (line mode)

a method of running SAS programs in which you enter one line of a SAS program at a time at the SAS session prompt. SAS processes each line immediately after you press the ENTER or RETURN key. Procedure output and informative messages are returned directly to your display device.

interface view engine

a type of SAS engine that SAS/ACCESS software uses to retrieve data from files that have been formatted by another vendor's software. Each SAS/ACCESS interface has its own interface view engine, which reads the interface product data and returns the data in a form that SAS can understand (that is, in a SAS data set). See also engine.

library member

any of several types of SAS file in a SAS library. A library member can be a data set, a view, a catalog, a stored program, or an access descriptor.

library reference

See libref.

libref (library reference)

a SAS name that is associated with the location of a SAS library. For example, in the name MYLIB.MYFILE, MYLIB is the libref, and MYFILE is a file in the SAS library. See also SAS library.

line mode

See interactive line mode.

member name

a name that is assigned to a SAS file in a SAS library. See also member type.

member type

a SAS name that identifies the type of information that is stored in a SAS file. Member types include ACCESS, AUDIT, DMBD, DATA, CATALOG, FDB, INDEX, ITEMSTOR, MDDB, PROGRAM, UTILITY, and VIEW.

missing value

a type of value for a variable that contains no data for a particular row or column. By default, SAS writes a missing numeric value as a single period and a missing character value as a blank space. See also null value.

null value

a special value that indicates the absence of information. Null values are analogous to SAS missing values. See also missing value.

object

any entity that can be manipulated by the commands of a programming language. Examples are values, variables, functions, and data structures.

observation

a row in a SAS data set. All of the data values in an observation are associated with a single entity such as a customer or a state. Each observation contains either one data value or a missing-value indicator for each variable.

pass-through facility

See SQL pass-through facility.

predicate

a component of a SAS WHERE statement or a component of an SQL WHERE or HAVING clause that is used in view descriptor selection criteria.

PROC SQL view

a SAS data set that is created by the SQL procedure. A PROC SQL view contains no data. Instead, it stores information that enables it to read data values from other files, which can include SAS data files, SAS/ACCESS views, DATA step views, or other PROC SQL views. The output of a PROC SQL view can be either a subset or a superset of one or more files. See also SAS data view.

query

a set of instructions that requests particular information from one or more data sources.

RDBMS

See relational database management system.

referential integrity

a set of rules that a DBMS uses to ensure that whenever a data value in one table is changed, the appropriate change is also made to any related values in other tables or in the same table. Referential integrity is also used to ensure that related data is not deleted or changed accidentally.

relational database management system (RDBMS)

a database management system that organizes and accesses data according to relationships between data items. The main characteristic of a relational database management system is the two-dimensional table. Examples of relational database management systems are DB2, Oracle, SAP ASE, and Microsoft SQL Server.

rollback

a data recovery process that restores a database after a hardware or software failure, or that returns it to a state before changes were made. See also commit.

SAS data file

a type of SAS data set that contains data values as well as descriptor information that is associated with the data. The descriptor information includes information such as the data types and lengths of the variables, as well as the name of the engine that was used to create the data. See also SAS data set, SAS data view.

SAS data set (data set)

a file whose contents are in one of the native SAS file formats. There are two types of SAS data sets: SAS data files and SAS data views.

SAS data view (data view)

a type of SAS data set that retrieves data values from other files. A SAS data view contains only descriptor information such as the data types and lengths of the variables (columns) plus other information that is required for retrieving data values from other SAS data sets or from files that are stored in other software vendors' file formats.

SAS engine

See engine.

SAS file

a specially structured file that is created, organized, and maintained by SAS. A SAS file can be a SAS data set, a catalog, a stored program, an access descriptor, a utility file, a multidimensional database file, a financial database file, a data mining database file, or an item store file.

SAS function (function)

a type of SAS language element that is used to process one or more arguments and then to return a result that can be used in either an assignment statement or an expression.

SAS index (index)

a component of a SAS data set that enables SAS to access observations in the SAS data set quickly and efficiently. The purpose of SAS indexes is to optimize WHERE-clause processing and to facilitate BY-group processing.

SAS informat (informat)

a type of SAS language element that is used to read data values according to the data's type: numeric, character, date, time, or timestamp.

SAS library

one or more files that are defined, recognized, and accessible by SAS, and that are referenced and stored as a unit. Each file is a member of the library.

SAS metadata

metadata that is created by SAS software. Metadata that is in SAS Open Metadata Architecture format is one example.

SAS variable (variable)

a column in a SAS data set or in a SAS data view. The data values for each variable describe a single characteristic for all observations (rows).

serde

an interface that enables serialization or deserialization of one or more file formats.

server

software that provides either resources or services to requesting clients, possibly over a network.

SQL

See Structured Query Language.

SQL pass-through facility (pass-through facility)

the technology that enables SQL query code to be passed to a particular DBMS for processing.

Structured Query Language (SQL)

a standardized, high-level query language that is used in relational database management systems to create and manipulate objects in a database management system. SAS implements SQL through the SQL procedure.

temporal data

event data that occurs at a particular date and time, such as an account inquiry. Temporal data is often referred to as time-sensitive data.

trigger

a type of user-defined stored procedure that is executed whenever a user issues a data-modification command such as INSERT, DELETE, or UPDATE for a specified table or column. Triggers can be used to implement referential integrity or to maintain business constraints. See also referential integrity.

type

See data type.

variable

See SAS variable.

view

a definition of a virtual data set that is named and stored for later use. A view contains no data; it merely describes or defines data that is stored elsewhere.

view descriptor

a SAS/ACCESS file that defines part or all of the DBMS data that is described by an access descriptor. See also access descriptor.

windowing procedure

a SAS procedure that you can use by entering information in one or more windows or dialog boxes. For example, the FSVIEW procedure is a windowing procedure. Some procedures, such as ACCESS and DBLOAD, can be used either as windowing procedures or in batch mode.