Glossary

This glossary defines SAS software terms that are used in this document as well as terms that relate specifically to SAS/ACCESS software.

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.

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.

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.

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

an attribute of every column in a table or database. The data type tells the operating system how much physical storage to set aside for the column, and specifies what type of data the column will contain. It is similar to the type attribute of SAS variables.

data value

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

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

a software application that enables you to create and manipulate data that is stored in the form of databases. Short form: DBMS.

DB2 catalog

a set of tables that DB2 maintains for its own use. These tables contain information about the other objects your DB2 system manages.

DBMS

a software application that enables you to create and manipulate data that is stored in the form of databases. Short form: DBMS.

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.

explicit pass-through

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

foreign key

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.

format

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

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.

Hadoop Distributed File System

a framework for managing files as blocks of equal size, which are replicated across the machines in a Hadoop cluster 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 the particular DBMS for processing.

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.

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. Short form: informat.

interactive 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).

key column

in Oracle, a column in a table that is used to create an index on the table. The column contains a unique data value for each row in a table.

libref

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.

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.

member

a SAS file in a SAS library.

member name

a name that is assigned to a SAS file in a SAS library.

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.

null value

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

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

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

query

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

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, Sybase, and Microsoft SQL Server.

referential integrity

a set of rules that a DBMS uses to ensure that a change to a data value in one table also results in a change 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

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, Sybase, 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.

row

in relational database management systems, the horizontal component of a table. A row is analogous to a SAS observation.

SAS/ACCESS view

a type of file that retrieves data values from files that are stored in other software vendors' file formats. You use the ACCESS procedure of SAS/ACCESS software to create SAS/ACCESS views.

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.

SAS 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

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. Short form: data view.

SAS file

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. Short form: data view.

SAS format

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

SAS 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 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. Short form: informat.

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

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. [plural: serdes]

server

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

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. Short form: SQL.

SQL pass-through facility

the technology that enables SQL query code to be passed to a particular DBMS for processing. Short form: pass-through facility.

SSID

the unique name that identifies each DB2 subsystem on your machine. Short form: SSID.

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. Short form: SQL.

subsystem ID

the unique name that identifies each DB2 subsystem on your machine. Short form: SSID.

table space

a named DB2 object that identifies sets of pages where records for one or more tables are stored. (A page is a 4K-byte or 32K-byte unit of storage within a table space.)

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.

term

an attribute of every column in a table or database. The data type tells the operating system how much physical storage to set aside for the column, and specifies what type of data the column will contain. It is similar to the type attribute of SAS variables.

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).

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.