client session
a SAS session that is running on a client computer. A client session accepts SAS
statements and passes those that are submitted to the server for processing. The client
session manages the output and messages from both the client session and the server
session.
column input
in the DATA step, a style of input in which column numbers are included in the
INPUT statement to tell SAS which columns contain the values for each variable.
This style of input is useful when the values for each variable are in the same
location in all records.
column output
in the DATA step, a style of output that specifies column numbers in the PUT
statement for writing data in fixed columns.
column-binary data storage
an older form of data storage that is no longer widely used and is not needed by most
SAS users. Column-binary data storage compresses data so that more than 80 items
of data can be stored on a single punched card. Because multi-punched decks and
card-image data sets remain in existence, SAS provides informats for reading
column-binary data.
command-style macro
a macro that is defined with the CMD option in the %MACRO statement.
comment
See comment statement
comment statement
information that is embedded in a SAS program and that serves as explanatory text.
SAS ignores comments during processing but writes them to the SAS log. Comment
syntax has several forms. For example, a comment can appear as a statement that
begins with an asterisk and ends with a semicolon, as in * message ;.
compilation
See program compilation
composite index
an index that locates observations in a SAS data set by examining the values of two
or more key variables.
compound expression
an expression that contains more than one operator.
compound WHERE expression
a WHERE expression that contains more than one operator, as in WHERE X=1 and
Y>3.
condition
in a SAS program, one or more numeric or character expressions that result in a
value on which some decision depends.
configuration file
an external file containing the SAS system options that define the environment in
which to run SAS. These system options take effect each time you invoke SAS.
784 Glossary
constant
in SAS software, a number or a character string that indicates a fixed value.
constant text
the character strings that are stored as part of a macro or as a macro variable's value
in open code, from which the macro processor generates text to be used as SAS
statements, display manager commands, or other macro program statements.
controller
a computer component that manages the interaction between the computer and a
peripheral device such as a disk or a RAID. For example, a controller manages data
I/O between a CPU and a disk drive. A computer can contain many controllers. A
single CPU can command more than one controller, and a single controller can
command multiple disks.
correlation
a relationship between two variables in which there is a tendency for the values of
one variable to become larger or smaller as the values of the other variable increase
or decrease.
correlation coefficient
a statistic that measures the strength of the linear relationship between two series of
values. The values of correlation coefficients range from -1 to 1.
CPU
See central processing unit
CPU time
the amount of time it takes for the central processing unit of a computer system to
perform the calculations or other operations that you request.
Cross-Environment Data Access
a feature of SAS software that enables a SAS data file that was created in a
directory-based operating environment to be read by a SAS session in another
directory-based environment.
data control block
on IBM mainframe operating systems such as z/OS, a storage area that contains
information about the physical characteristics of an operating system data set.
data error
a type of execution error that occurs when a SAS program analyzes data that
contains invalid values. For example, a data error occurs if you specify numeric
variables in the INPUT statement for character data. SAS reports these errors in the
SAS log but continues to execute the program.
data partition
a physical file that contains data and which is part of a collection of physical files
that comprise the data component of a SAS Scalable Performance Data Engine data
set.
data representation
the form in which data is stored in a particular operating environment. Different
operating environments use different standards or conventions for storing floating-
point numbers (for example, IEEE or IBM 390); for character encoding (ASCII or
EBCDIC); for the ordering of bytes in memory (big Endian or little Endian); for
Glossary 785
word alignment (4-byte boundaries or 8-byte boundaries); and for data-type length
(16-bit, 32-bit, or 64-bit).
data set
See SAS data set
data set option
See SAS data set option
DATA step
in a SAS program, a group of statements that begins with a DATA statement and that
ends with either a RUN statement, another DATA statement, a PROC statement, or
the end of the job. The DATA step enables you to read raw data or other SAS data
sets and to create SAS data sets.
DATA step interface
a feature of SAS software that enables you to use the DATA step to interact with
other components of SAS, such as the macro facility or the Output Delivery System
(ODS).
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 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
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.
date and time format
instructions that tell SAS how to write numeric values as dates, times, and datetimes.
date and time informat
the instructions that tell SAS how to read numeric values that are represented as
dates, times, and datetimes.
date constant
See SAS date constant
date interval
a unit of measurement that SAS can count within an elapsed period of days or
months.
786 Glossary
date value
See SAS date value
datestamp
the date of a transaction that is recorded by the computer. Examples include the date
at the beginning of the SAS log or the printed date on an output file; the initialization
of a SAS session; and the creation or change of a SAS file.
datetime constant
See SAS datetime constant
datetime interval
a unit of measurement that SAS can count within an elapsed period of hours,
minutes, seconds, days, and months.
datetime value
See SAS datetime value
DBMS
See database management system
DCB
See data control block
declarative statement
a statement that supplies information to SAS and that takes effect when the system
compiles program statements.
default directory
the directory that you are working in at any given time. When you log in, your
default directory is usually your home directory.
delimiter
a character that serves as a boundary that separates the elements of a text string.
delimiter-sensitive data
data in which the individual data values contain embedded delimiters, such as
quotation marks, commas, and tabs.
descriptive statistic
a quantity that characterizes, rather than draws inference from, a collection of values.
Types of descriptive statistics are measures of central tendency, measures of variation
among values, and measures of the shape of the distribution of values.
descriptor information
information about the contents and attributes of a SAS data set. For example, the
descriptor information includes the data types and lengths of the variables, as well as
which engine was used to create the data. SAS creates and maintains descriptor
information within every SAS data set.
destination
See ODS destination
DICTIONARY table
any of a number of read-only SAS data views that provide information about SAS
data libraries, SAS data sets, SAS macros, and external files that are either in use or
Glossary 787
available in the current SAS session. A DICTIONARY table also contains the
settings for SAS system options that are currently in effect.
direct access
a technique for retrieving data records in a data set directly, rather than by searching
a data set sequentially to find a match. In table lookup applications, records are
retrieved by observation number.
disk
a device for data storage that enables you to access any record on the disk directly.
Disk storage differs from tape storage, which enables only sequential processing of
records.
DO group
a sequence of statements that starts with a simple DO statement and that ends with a
corresponding END statement.
DO loop
a sequence of statements that starts with an iterative DO, DO WHILE, or DO UNTIL
statement and that ends with a corresponding END statement. The statements are
executed (usually repeatedly) according to directions that are specified in the DO
statement.
DOCUMENT destination
a SAS Output Delivery System (ODS) destination that produces a hierarchy of
output objects. The DOCUMENT destination enables users to render multiple ODS
output formats without rerunning a PROC step or DATA step, and it gives users
more control over the structure of the output.
double trailing at sign
a special symbol @@ that is used to hold a line of data in the input buffer during
multiple iterations of a DATA step.
DSD
See delimiter-sensitive data
EBCDIC collating sequence
the rules that are used by a specific EBCDIC encoding for sorting textual data. Sort
order is determined by the location of each code point in the code page of an
EBCDIC encoding. For example, in the German EBCDIC code page, the sort order
of precedence is punctuation characters, numbers, uppercase characters, and
lowercase characters.
elapsed time
the amount of clock time needed to receive the result of a computer program,
including time used by the computer to execute your program and the time your
program spends waiting for resources (such as memory or a printer).
encryption
the act or process of converting data to a form that is unintelligible except to the
intended recipients.
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.
788 Glossary
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