|
| DASD—direct access storage device |
|
A
data storage unit where data can be accessed directly without having to
progress through a serial file such as a magnetic tape. |
|
| Data
Definition Language (DDL) |
|
SQL
statements that create, modify, and remove database objects such as tables,
indexes, and users. Common DDL statements are CREATE, ALTER, and DROP. |
|
| data
dictionary |
|
A
database containing information (metadata) relating to data elements, databases,
files, and programs and that catalogs all data elements, including their
names, structures, and usage. |
|
| data
element |
|
The
most elementary unit of data that can be identified and described in a dictionary
or repository which cannot be subdivided. |
|
| data
extract |
|
A
subset of data extracted from one environment and transported to another
environment. |
|
| data
flow diagram |
|
A
diagram that shows the normal flow of data between services as well as the
flow of data between data stores and services. |
|
| data
integrity |
|
The
quality of the data residing in the database objects. Constraints on the
database tables enforce integrity rules. |
|
| Data
Manipulation Language (DML) |
|
SQL
statements that query and amend the database data. Common DML statements
include SELECT, INSERT, UPDATE, and DELETE. |
|
| data
mart |
|
A
data warehouse that is designed for a particular line of business, such
as sales, marketing, or finance. |
|
| data
migration tools |
|
Unspecified
tools that allow data to be moved from various sources into a data warehouse. |
|
| data
mining |
|
A
technique that discovers meaningful patterns and relationships hidden in
data, often used for segmenting customers and predicting their behavior.
(See also knowledge discovery.) |
|
| data
model |
|
A
representation of the specific information requirements of a business area.
See also entity relationship diagram. |
|
| data
warehouse |
|
A
relational database that is designed for query and analysis rather than
transaction processing. A data warehouse usually contains historical data
that is derived from transaction data, but it can include data from other
sources. It separates analysis workload from transaction workload and enables
a business to consolidate data from several sources. In addition to a relational
database, a data warehouse environment often consists of an ETT solution,
an OLAP engine, client analysis tools, and other applications that manage
the process of gathering data and delivering it to business users. See
also ETT and OLAP. |
|
| data
warehouse method (DWM) |
|
A
structured method for the full lifecycle custom development of data warehouse
projects. |
|
| database |
|
A
collection of data, usually in the form of tables or files, under the control
of a database management system (DBMS). |
|
| database
administrator (DBA) |
|
Person
responsible for administering, monitoring, and maintaining the database. |
|
| database
management system (DBMS) |
|
The
component of a database that controls all user and system activities related
to the core functions of the database, such as security checking, tablespace
allocation, and space management. |
|
| DBA—database administrator |
|
Person
responsible for administering, monitoring, and maintaining the database. |
|
| DBMS—database management system |
|
The
component of a database that controls all user and system activities related
to the core functions of the database, such as security checking, tablespace
allocation, and space management. |
|
| DDL—Data Definition Language |
|
SQL
statements that create, modify, and remove database objects such as tables,
indexes, and users. Common DDL statements are CREATE, ALTER, and DROP. |
|
| decentralized
warehouse |
|
A
remote data source that users can query/access via a central gateway that
provides a logical view of corporate data in terms users can understand.
The gateway parses and distributes queries in real time to remote data sources
and returns result sets back to users. |
|
| decision
support |
|
The
act of using data and tools within an organization to support managerial
decisions. Usually decision support involves the analysis of many units
of data in a heuristic fashion. |
|
| decision
support system (DSS) |
|
A computer program that analyzes business data and presents it so that users can make business decisions more easily. |
|
| definition |
|
The
description of a database object that includes characteristics such as the
object's data type, dimensions, long description, name, permission specifications, properties, and type (e.g., dimension or variable). |
|
| delta |
|
The
change. A file created by an application that contains only changes made
to the application. |
|
| denormalization |
|
In
a relational database, the process of structuring the schema to enhance
performance by introducing redundant data. Denormalization is frequently
accomplished by eliminating joins. Contrast with normalization. |
|
| denormalized
data |
|
The
data in a denormalized database model. |
|
| dependent
data mart |
|
A
data mart that is sourced directly from a data warehouse. |
|
| derived
column |
|
A
value derived by some algorithm from the values of other columns. |
|
| derived
data |
|
Data
that exists only as a subset of other data. |
|
| derived
fact (or measure) |
|
A
fact (or measure) that is generated from existing data using a mathematical
operation or a data transformation. Examples include averages, differences, percentages, and totals. See also fact data. |
|
| descendant |
|
A
value at any level below a given value in a hierarchy. |
|
| Designer
(Oracle Designer) |
|
An
Oracle computer-aided systems engineering (CASE) tool. |
|
| detail
data |
|
Measurements
in the core of a data warehouse on which all online analytical processing
(OLAP) queries depend. Synonymous with fact data. |
|
| Developer
(Oracle Developer) |
|
The
Oracle application-building tool for query, reporting, database manipulation,
and graphical display of database values. |
|
| Digerati |
|
The digital version of
Literati, referring to those people knowledgeable about the digital
revolution. |
|
| digital subscriber
line (DSL) |
|
Technology for transmitting high-bandwidth
content over copper wire. |
|
| dimension |
|
A
construct in a multidimensional structure that represents a side of
a multidimensional cube. Each dimension represents a different category
that the business chooses to measure, such as customer, region, product,
and time. |
|
| dimension
data |
|
The data by which the user queries
the business measures. See also fact data, dimension table, and fact table. |
|
| dimension
hierarchy |
|
A logical structure that
uses ordered levels. Synonymous with hierarchy. |
|
| dimension
label |
|
In a database table, a
text description for a dimension. For example, a dimension named GEOGRAPHY
might have the label Geographic Areas and display the label, rather than
the name, in reports, tables, and graphs. |
|
| dimension
table |
|
A
table in a star model that is joined to the fact table by a key value. |
|
| dimension
value |
|
One
element in the list that makes up a dimension. For example, members in the
Geography dimension might include Boston and Paris. |
|
| dimension
value label |
|
A text description for
a dimension value. For example, a PRODUCT dimension might have a value called
"LAPPC," the label for which is "Laptop PC." Dimension
value labels might appear as row, column, and page labels in reports or
tables and as tick labels in graphs. |
|
| dimensional
model |
|
A
model that supports a top-down design methodology. For each business process,
the dimensional model determines relevant facts and dimensions. |
|
| direct
access storage device (DASD) |
|
A
data storage unit where data can be accessed directly without having to
progress through a serial file such as a magnetic tape. |
|
| dirty data |
|
Data that is in an unfit state to be loaded into a data warehouse and that must be transformed or cleansed. |
|
| Discoverer (Oracle Discoverer) |
|
The Oracle end-user analysis, query, and reporting tool that is particularly good for use in the data warehousing environment. |
|
| distributed
application |
|
An application made up
of distinct components running in separate runtime environments, usually
on different platforms connected via a network. Typical distributed applications
are two-tier (client/server), three-tier (client/middleware/server), and
n-tier (client/multiple middleware/multiple servers). |
|
| DML—Data Manipulation Language |
|
SQL statements that query
and amend the database data. Common DML statements include SELECT, INSERT,
UPDATE, and DELETE. |
|
| domain name |
|
The unique name that identifies
an internet site. Domain names always have two or more parts separated
by dots. |
|
| drill |
|
The process of navigating from one item to a set
of related items. Drilling typically involves navigating up and down through
the levels in a hierarchy. See also drill-across, drill-down, drill-up |
|
| drill-across |
|
An analytical technique that queries data from two or more fact tables in a single report. |
|
| drill-down |
|
An analytical technique that queries data from a summary row and navigates through a hierarchy of data to reach the detail-level rows. |
|
| drill-up |
|
An
analytical technique that navigates from detail to header rows of data used
to view summarized or aggregated data. |
|
| DSL—digital subscriber line |
|
Technology for transmitting
high-bandwidth content over copper wire. |
|
| DSS—decision support system |
|
A computer program that
analyzes business data and presents it so that users can
make business decisions more easily. |
|
| DWM—data warehouse method |
|
A structured method for
the full lifecycle custom development of data warehouse projects. |
|
