A
Access Module Processor
See AMP.
access right
A user's right to perform the Teradata SQL statements against a table, database, user, macro, or view. Also known as privilege.
action definition
A logical action consisting of a single physical action and related attributes.
aggregate UDF
In contrast to a scalar UDF, an aggregate UDF returns a single result that represents information about one or more sets of relational data. The row sets are created by way of grouping clauses in an SQL statement. Like scalar functions, the aggregate functions can appear anywhere in an SQL expression that built-in aggregate functions can. Aggregate functions can also be passed column references and literal values. Some examples of common aggregate functions are SUM, AVG, MIN, and MAX. Aggregate functions can save context or state between invocations.
Alert Policy Editor
A component used to define alert policies: create actions, set event thresholds, assign actions to events, and apply the policy to Teradata Database.
American National Standards Institute
See ANSI.
American Standard Code for Information Interchange
See ASCII.
AMP
Access Module Processor. A virtual processor that receives steps from a PE and performs database functions to retrieve or update data. Each AMP is associated with one vdisk, where the data is stored. An AMP manages only its own vdisk and not the vdisk of any other AMP.
ANSI
American National Standards Institute. ANSI maintains a standard for SQL. For information about Teradata compliance with ANSI SQL, see SQL Fundamentals.
ASCII
American Standard Code for Information Interchange. Pronounced as-key. A character set used primarily on personal computers.
B
Basic Teradata Query
See BTEQ.
BTEQ
Basic Teradata Query. A utility that allows users on a workstation to access data on a Teradata Database. BTEQ commands are used for controlling sessions, submitting Teradata SQL requests, formatting results, and handling output data. BTEQ can also be used to verify the installation of Teradata client utilities.
C
Call-Level Interface , Version 2
See CLIv2.
central processing unit
See CPU.
character set
A grouping of alphanumeric and special characters used by computer systems to support different user languages and applications. Various character sets have been codified by ANSI.
CLIv2
Call-Level Interface, Version 2. A library of routines that enable an application program to access data stored in Teradata Database.
coexistence system
A Teradata Database system running on mixed platforms.
CPU
Central Processing Unit. The part of a computer which controls all the other parts. CPUs are not physically associated with vprocs.
D
data dictionary
The Teradata Database Data Dictionary is composed of tables and views that reside in the system database. The system reserves these tables and views for use and they contain information about the system’s associated data. Data Dictionary system tables include current definitions, control information, and general information.
data source name
See DSN.
database administrator
See DBA.
database computer
See DBC.
database query log
See DBQL.
database tree
An alphabetical listing that displays all the databases and objects in the selected root database of the connected Teradata Database server. It is located on the left side of the Teradata Administrator main window.
DBA
Database Administrator. Generally, a person responsible for the design and management of one or more databases and for the evaluation, selection and implementation of database management systems.
DBC
Database Computer. A dedicated relational database management computer.
DBQL
Database Query Log. A series of system tables, created in the DBC database during Teradata Database installation, used to track query processing. See Database Administration to learn more about the DBQL.
distinct UDT
Based on a single predefined data type such as INTEGER or VARCHAR, a distinct UDT is basically a redefinition of an already predefined SQL data type.
DLL
Dynamic Link Library. A .dll file contains a library of functions and other information that can be accessed by a Windows program. When a program is launched, links to the necessary .dll files are created. If a static link is created, the .dll files are in use as long as the program is active. If a dynamic link is created, the .dll files are only used when needed. Dynamic links help programs use resources, such as memory and hard drive space, more efficiently.
DSN
Data Source Name. The logical name used by Open Database Connectivity (ODBC) to refer to the drive and other information that is required to access data. The name is used by Internet Information Services (IIS) for a connection to an ODBC data source. Use the ODBC Data Source Administrator to set this name.
dynamic link library
See DLL.
E
EBCDIC
Extended Binary Coded Decimal Interchange Code. A standard method of assigning binary (numeric) values to alphabetic, numeric, punctuation, and transmission-control characters.
Extended Binary Coded Decimal Interchange Code
See EBCDIC.
external role
A DBA can use a Teradata Database extension that adds the keyword prefix ‘EXTERNAL’ to create roles for directory users. After external roles have been created, they must assign (not GRANT) them to directory users. There are restrictions on external roles. For more information on external roles, see Database Administration, Security Administration, or SQL Data Definition Language.
external routine
A generic term for UDFs, table UDFs, UDMs, and external stored procedures.
external stored procedure
See XSP.
G
GMT
Greenwich Mean Time. The time at Greenwich, England, which is used as the basis for standard time throughout the world.
Greenwich Mean Time
See GMT.
grid area
Also referred to as the grid, it displays information about the database or database object that is selected in the database tree. It is located on the right side of the Teradata Administrator main window and can have up to two displays in the upper and lower portions of the grid.
H
HTML
Hypertext Markup Language. The coding language used to create hypertext documents for use on the World Wide Web.
Hypertext Markup Language
See HTML.
I
Input/Output
See I/O.
Internet Protocol
See IP.
I/O
Input/Output. Communication between a computer and its users, its storage devices, other computers (over a network) or the outside world. The devices the computer uses to do this are called peripherals.
IP
Internet Protocol. Data transmission standard. The standard that controls the routing and structure of data transmitted over the Internet.
L
logical action
A named action that is defined on the Alert Policy Editor's Actions tab. Logical actions can be assigned to events in the alert policy.
O
ODBC
Open Database Connectivity. Type of driver used to connect applications with databases. The ODBC driver processes ODBC calls from an application, but passes SQL requests to the Teradata Database for processing.
Open Database Connectivity
See ODBC.
P
permanent space
Commonly referred to as perm space. All databases have a defined upper limit of perm space. Perm space is the maximum amount of space available for tables. Perm space is not pre-allocated; a limit is just allocated.
privilege
A user's right to perform the Teradata SQL statements against a table, database, user, macro, or view. Also known as access right. See access right.
Procedure Builder
Provides a list of valid statements for building the logic of a stored procedure. This feature is available in Teradata SQL Assistant for Microsoft Windows and Teradata SQL Assistant/Web Edition.
profile
A set of parameters assigned to a user, a group of users, or an account that determines what scheduling capabilities are available.
Q
Query Builder
A tool that to create statements to add to the Query window. This tool is available in Teradata SQL Assistant for Microsoft Windows and Teradata SQL Assistant/Web Edition.
S
scalar UDF
A scalar UDF accepts input by way of its argument list and returns a single result value. It can be used wherever a value expression of the same type as its declared return value is allowed. The Teradata Database also allows UDFs to be called in a SELECT statement without a table name. The function is invoked once, in parallel, for each result row in a query when the SQL expression is evaluated. Some examples of built-in Teradata Database SQL scalar functions include CHARACTER_LENGTH, ABS, and SQRT. Scalar functions do not save context or state between invocations.
session
A session begins when the user logs on to Teradata Database and ends when the user logs off Teradata Database. In client software, a logical connection between an application program on a host and Teradata Database. The connection permits the application program to send one request at a time to and receive one response at a time from Teradata Database.
Single Sign On
See SSO.
skew
This value is calculated based on a single database collection interval. If the session
collection rate is 60, then the skew is calculated for a 60 second period. The value
is calculated using current data values. For example, the max CPU used during the
past 60 seconds relative to the average used over that same 60 seconds:
skew = 100 * (1 - avg/max).
spool space
Temporary space used to hold intermediate query results or formatted answer sets to queries. After the query is complete, the spool space is released. All databases have an upper limit of spool space. If no limit is defined for a particular database or user, limits are inherited from parents.
SQL
Structured Query Language. Standardized query language for requesting information from a database. SQL consists of a set of facilities for defining, manipulating, and controlling data in a relational database.
SSO
Single Sign On. An authentication option that allows Teradata Database on Windows 2000 users to access Teradata Database based on authorized network usernames and passwords. This feature simplifies the procedure requiring users to enter an additional username and password when logging on to Teradata Database using client applications.
startup string
One or more Teradata SQL statements, separated by semicolons, that are executed to establish the initial session environment when the user logs on.
Structured Query Language
See SQL.
structured UDT
A collection of fields called attributes, each of which is defined as a predefined data type or other UDT (which allows nesting).
T
TDPID
Teradata Director Program Identifier. The name of the Teradata Database being accessed or monitored.
temporary space
Commonly referred to as temp space. Temp space is used for global and volatile temporary tables, and these results remain available to the user until the session is terminated. Tables created in temp space do survive a restart.
Teradata Director Program Identifier
See TDPID.
Teradata Tools and Utilities
See TTU.
TTU
Teradata Tools and Utilities. A set of software tools and utilities used for connecting to a Teradata Database, as well as loading, unloading, accessing, managing, manipulating, and storing data.
U
UDF
User-Defined Function. By providing a mechanism that supports the creation of SQL functions, scalar and aggregate UDFs allow users to add their own extensions to Teradata Database SQL. These functions can be used to operate on any Teradata Database data type and can be utilized wherever built-in functions are used. If a function doesn’t exist to perform a specific task or algorithm, write one that does. UDFs can also simplify complex SQL syntax.
UDM
User-Defined Method. A special kind of user-defined function (UDF) that is associated with a UDT. The term method and the acronym UDM are interchangeable. Teradata Database supports two types of UDMs: Instance and Constructor.
UDT
User-Defined Type. Allow users to create custom data types that model the structure and behavior of data in their applications.
UTF8 or UTF16
Unicode Translation Format, 8 bit or 16 bit. The name of a Teradata Client Character Set.
user-defined functions
See UDF.
user-defined methods
See UDM.
user-defined types
See UDT.
Unicode Translation Format, 8 bit or 16 bit
See UTF8 or UTF16.
X
XSP
External Stored Procedure. Defined and stored as a database object. The XSP attributes are stored in the DBC.TVM data dictionary table. Similar to the user-defined function objects, the source code and the object code of external stored procedures are stored in the database of the user space.