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Transcript
Database
Vocabulary
Terms
Vicki McKenzie
DATABASE
Often abbreviated DB. A collection of information
organized in such a way that a computer
program can quickly select desired pieces of
data. You can think of a it as an electronic filing
system.
Traditional they are organized by fields, records,
and files. A field is a single piece of information;
a record is one complete set of fields; and a file
is a collection of records. For example, a
telephone book is analogous to a file. It contains
a list of records, each of which consists of three
fields: name, address, and telephone number.
FIELD(S)
A space allocated for a particular item of
information. A tax form, for example, contains a
number of these: one for your name, one for
your Social Security number, one for your
income, and so on. In database systems, these
are the smallest units of information you can
access.
Most of these have certain attributes associated
with them. For example, some fields are
numeric whereas others are textual, some are
long, while others are short. In addition, every
one of these has a name.
RECORD(S)
In database management systems, a
complete set of information. They are
composed of fields, each of which
contains one item of information. A set of
these constitutes a file. For example, a
personnel file might contain a set of these
that have three fields: a name field, an
address field, and a phone number field.
DATA ENTRY
The process of entering data into a
computerized database or spreadsheet. It
can be performed by an individual typing at a
keyboard or by a machine entering data
electronically.
LIST
To display data in an
ordered format.
Any ordered set of data.
SORT
A term used to describe the
process of organizing data in a
particular order allowing for
information to be found easier. For
example, names and contact
information may be organized in
alphabetical order to allow the
person looking for a name to
quickly see if it is available.
ASCENDING/ ALPHABETICAL /
NUMERICAL
An order of information from
lowest to highest, such as
1,2,3,4,5,6,7,8,9,10
OR
A,B,C,D,E,F. . .
DESCENDING
An order of information from
highest to lowest, such as
10, 9, 8. 7, 6, 5, 4, 3, 2, 1
OR
Z,Y, X, W, V, U. . .
KEYWORD
In text editing and database
management systems, this is
an index entry that identifies a
specific record or document.
A word used by a search
engine in its search for relevant
Web pages.
SEARCH/ FILTER/ QUERY
A pattern through which data
is passed. Only data that
matches the pattern is
allowed to pass through the
this action.
To make a request for
information from a database.
DATABASE SEARCH
STRATEGY
A request for information from a database. There are
three general methods for posing filters (queries):
Choosing parameters from a menu: In this method, the
database system presents a list of parameters from
which you can choose. This is perhaps the easiest
way to pose a filter (query) because the menus
guide you, but it is also the least flexible.
Query by example (QBE): In this method, the system
presents a blank record and lets you specify the
fields and values that define the filter (query).
OPERATIONS
Comparison: <, >,=,
< >,<=, >=, is empty, is not
empty.
REPORTS
A formatted and organized
presentation of data. Most
database management
systems include a writer that
enables you to design and
generate these.
LAYOUT
In database management
systems, this refers to the
way information is displayed.
You can change this by
selecting different fields.
FORMAT
A specific pre-established
arrangement or organization of
data. Data in a file is stored in this
way and is established by whatever
application created the file (i.e.,
organized the data) and typically
needs to be read by the same or
similar program that can interpret
the this and present the data to the
user on the computer screen.
CRITERIA
This allows you to specify filtering
(query) options — such as which
data columns to display, how to
order the results, and what rows
to select — by entering your
choices into a spreadsheet-like
grid.
ONE CRITERION
You can specify the data rows that appear in your
filter (query) by specifying search conditions.
You must specify search conditions using an
expression. Most commonly the expression consists
of an operator and a search value.
OPERATORS: =, <, >, etc.
For example, to find all the counties that have at
least 5,000 people, you would use a comparison of
> (greater than).
MULTIPLE CRITERION
You can specify the data rows that appear in your filter (query) by
specifying search conditions. This will have more than one condition
and utilize more than one field. You will use operators and connectors.
OPERATORS: =, <, >, etc.
CONNECTORS: AND, OR
For example, to find all the animals that have :
HEART CHAMBERS >(greater than) 3,AND, SIZE(IN.) = (equal to) 96
CITE SOURCES
The ethics of research demand that writers be
credited for their work and their writing. Not to do
so is to plagiarize, to intentionally or
unintentionally appropriate the ideas, language,
or work of another without sufficient
acknowledgement that such material is not one's
own.
RELATIONAL DATABASE
A type of database management
system that stores data in the form
of related tables. These are
powerful because they require few
assumptions about how data is
related or how it will be extracted
from the database. As a result, the
same database can be viewed in
many different ways.