Tuple: This is a mathemat
ical term for a finite sequence of n terms. For example, the set {1, 2, 3, 4}
is
a
four-tuple. A tuple is equivalent of a record. In RDBMS, a table has n tuples.
Unauthorized: Not permit
ted, illegal, unlawful.
View: A view is a virtual
table in the database defined by a query.
Transient: Temporary, t
ransitory, momentary.
Transaction: A group of
processing steps that are t reated as a single act ivity to achieve a desired
result
. In DBMS, collect ions of operat ions that form a single logical unit of work
are called
t
ransact ions. A database system ensures proper execut ion of t ransact ions
despite failures – either the
ent
ire t ransact ion executes, or none of it does.
Table: A table has a
specified number of columns but can have any number of rows. Rows stored in a
table
are st ructurally equivalent to records from flat f iles.
Tablespace: The
logical part of the database which represents collect ion of the st ructures
like tables,
etc
created by various users.
Superset: Given two sets, A and
B, A is a superset of B if all elements of B are also elements of A.
Every
set is a superset of itself, and every set is a superset of the empty set .
Static: Something which does
not change. (Example: the typical web page is stat ic in that it does not
change
unt il the webmaster physically alters the document .)
Software application designer: The person who designs software applicat ions.
Site: Geographical locat ion
Schema: A descript ion of a
database. It specifies (among other things) the relat ions, their at t ributes,
and
the domains of the at t ributes.
Requirement specification: A
document which contains requirement for a specific applicat ion.
Page: It is part of a table.
Usually in one page mult iple rows are stored.
Participating entities: The ent it
ies which are j oined by the relat ion.
Queries: A query is essent
ially a request that a user makes on the database.
Recovery: Restorat ion, return
to an original state.
Model: A representat ion or a
scaled down st ructure of an obj ect .
Jargons: The specialized or
technical language of a t rade, profession, or similar group.
Iterative: Process of repeat ing
the same task.
Integrity Constraints: A set of
rules to ensure the correctness and accuracy of data.
Integrated: United
into a larger unit . Brought together to form a sat isfactory and working whole
Homogeneous Network: A network
composed of systems of similar architecture and runs a single
network
layer protocol.
Heterogeneous Network: A network
that consists of workstat ions, servers, network interface cards,
operat
ing systems, and applicat ions f rom many vendors, all working together as a
single unit . The
network
may also use different media and different protocols over different network
links.
Entity: An ent ity is a “
thing” or “ obj ect ” in the real world that is dist inguishable from other obj
ects.
Example:
each person is an ent ity, and bank accounts can be considered to be ent it
ies.
End User: The person for whom a
system is being developed. Example: a bank teller or a bank manager
is
an end user of a bank system.
Distributed: A computer
system is dist ributed when different components and obj ects comprising an
applicat
ion can be located on different computers connected to a network.
Encryption: The
process of manipulat ion of data to prevent accurate interpretat ion by all but
those for
whom
the data is intended.
Cardinality of a relation: The
number of records / tuples in a table.
Backup: A second copy of a
file or set of files to be used in case the primary file(s) are dest royed or
corrupted.
Backups are essent ial for all but the most t rivial work. For crit ical work,
two backup sets
are
advisable
Anomaly: A departure from the
expected; an abnormality.
gud
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