Database Glossary

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ADD_MONTHS

Function that adds calendar months to a date.

Afficionado

An ardent follower, a fan, a buff, a devotee.

Aggregate

To gather into a sum or whole. 

Alias

Gives a table another name to simplify queries and improve performance

ALL operator

Compares value to every value returned by the subquery

ALTER SEQUENCE

Modifies a sequence.

ALTER TABLE

To add, modify, or drop columns from a table; use to add a constraint to existing tables with the ADD clause.   

ALTER USER

The right to change your password.

Ambiguous

Open to more than one interpretation.

AND

Both conditions must be true for a record to be selected.

ANSI

American National Standards Institute; sets standards for a wide range of technical areas.

ANY operator

Compares value to each value returned by the subquery.

Application

An application is a collection of database-driven Web pages linked together using tabs, buttons, or hypertext links

Application builder

Oracle's HTML DB web-based application developer tool used to design and assemble the Web based user interfaces on top of database objects such as table, views, and procedures.

Application software

Program that gives a computer instructions that provide the user with tools to accomplish a task.

Appreciation

A rise in value or price, especially over time

Arc

A curved line. An arc is used to represent an exclusive relationship in an entity-relationship diagram

Argument (arg)

A value used to evaluate a function.

Arithmetic expression

A mathematical equation.

Arithmetic operator

A symbol used to perform an operation on some values.

Artificial attribute

A created attribute that does not occur in nature (example: a student id).

Artificial UID

A unique identifier that does not occur in nature, usually an artificial attribute.

Ascending/ASC

Orders the rows in ascending order (this is the default order); A Z.

Assumption

Something taken for granted or accepted as true without proof; a supposition.

Attribute

Characteristic, something that describes, quantifies or specifies an entity.

Audit trail

A step-by-step record of data changes.

AVG

Calculates average value excluding nulls.

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Barred relationship

A relationship that participates in an entity's unique identifier.

BETWEEN

Displays rows based on a range of values.

BFILE

Binary data stored in an external file; up to 4 gigabytes.

BLOB

Binary large object data up to 4 gigabytes.

Browser

A program that accesses and displays files and other data available on the Internet and other networks.

Business rule

A formalized statement of the usual, customary, or generalized course of action or behavior for a business. A generalized statement that describes what is true in most or all cases.

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CACHE/NOCACHE

Specifies how many values the Server pre-allocates and keeps in memory.

Caches

A fast storage buffer in the central processing unit of a computer. Also called cache memory.

Cardinality

A property of an end of a relationship between X and Y, that describes how many of X is related to Y. Both ends of a relationship must have a defined cardinality. Same as degree.

Career portfolio

The materials collected over the course of a career, representative of a person's work.

Cartesian product

Results from an invalid or omitted join condition; all combinations of rows are displayed.

Cascade barred relationship

A series of barred relationships between successively connected entities. Cascade barred relationships imply that the unique identifier of each entity in the chain is carried down to the entity on the next level.

CASCADE constraint

Constraints referring to dropped columns will also be dropped.

CASE

Implements conditional processing (IF-THEN-ELSE logic) within a SQL statement; it meets the ANSI standard.

Case conversion functions

These functions convert case for character strings.

Case sensitive

There is a noted difference between big (capitalized) and small letters.

CEO

Chief Executive Officer, the highest-ranking executive in a company or organization, responsible for carrying out the policies of the board of directors on a day-to-day basis.

CHAR(size)

The CHAR data type stores fixed-length character strings. (Size) refers to the maximum number of characters. The database allocates a fixed space designated by (size), regardless of how many characters the actual data takes up. The default size is 1, the max size is 2000.

Character data type

Stores fixed-length character strings.

Character functions

Functions that accept character data as input and can return both character and numeric values.

Character manipulation functions

These functions manipulate character strings.

CHECK constraint

Specifies a condition that must be true for each row of data.

Child record

The record that holds the column data that references to another table.

Chronological resume

A document highlighting an individual's accomplishments and job experience, listed according to date (from the most recent employment to further in the past.)

Clause

Is a part of a SQL statement, one line of code.

Client

Customer. The party for which professional services are rendered.

CLOB

Character large object data up to 4 gigabytes.

COALESCE

Returns the first non-null expression in the list.

Column

A means of implementing an item of data within a table, an implementation of an attribute or relationship.

Column alias

Renames a column heading.

Column level constraint

References a single column and is defined within a specification for the owning column.

Comma (,)

Separation symbol for the columns of data.

COMMENT ON TABLE

Command to add comments to a table or column.

Commerce

The exchange or buying and selling of commodities; esp. the exchange of merchandise, on a large scale, between different places or communities.

COMMIT

Ends the current transaction by making al l pending data changes permanent

Commission

To engage and pay for the services of a professional (e.g., carpenter, writer, gardener).

Comparison conditions

Compares one expression to another value or expression.

Comparison/relational Operators

Symbols (>, <, >=, <=, =, <>) used to compare expressions.

Complex view

Derives data from more than one table, contains functions or groups of data, and does not always allow DML operations through the view.

Compliant

Yielding; bending; pliant; submissive.

Components

A constituent element, as of a system.

Composite

Made up of distinct parts.

Composite UID

A unique identifier that is a combination of attributes and/or relationships.

CONCAT

Merges the first character value to the second character value; equivalent to concatenation operator (||).

Concatenation

Links two columns together to form one character data column.

Conceptual model

A data model, usually represented by an entity-relationship diagram.

Conditional expressions

Implement IF-THEN-ELSE logic.

Conditional nontransferability

Refers to a relationship that may or may not be transferable, depending on time.

Constant

A quantity assumed to have a fixed value in a specified mathematical context.

Constraint

Restricts, limits, or regulates; a check. A restriction that applies to data, which is often dictated by the business rules. 

Consultant

One who gives expert or professional advice.  In the information technology industry, one who provides expert services, such as data modeling, database troubleshooting, installation support, etc.

Context

The circumstances in which an event occurs; a setting.

Convention

A practice or procedure widely observed in a group, especially to facilitate communication or social interaction; a custom.

Conversion

A change in the units or form of an expression.

Conversion functions

Functions that convert a value from one data type to another.

Coordinated universal time (UTC)

Is standard time expressed using a 24-hour clock.

Correlation

The simultaneous change in value of two numerically valued random variables.

Corresponding

To be similar in character, quantity, origin, structure, or function.

COUNT

Returns the number of rows with non-null values for the expression.

CREATE INDEX

Creates an index.

CREATE OR REPLACE VIEW

Recreates or creates a view.

CREATE PROCEDURE privilege

The right to create a stored procedure, function, or package in the user’s schema.

CREATE PUBLIC SYNONYM

To refer to a table by another name to simplify access.

CREATE ROLE

The right to create a role.

CREATE SEQUENCE

Command that automatically generates sequential numbers.

CREATE SEQUENCE privilege

The right to create a sequence in the user’s schema.

CREATE SESSION privilege

The right to connect to the database.

CREATE TABLE

Command to create tables to store data.

CREATE TABLE privilege

The right to create tables in the user’s schema.

CREATE USER

The right to create other users.

CREATE VIEW

Creates a view by embedding a subquery within it.

CREATE VIEW privilege

The right to create a view in the user’s schema.

CROSS JOIN

Returns the Cartesian product from two tables.

CRUD analysis

The practice of checking a data model for create, retrieve, update and delete functions that the business requires.

Culminating

To come to completion, to reach the highest point or degree.

CURRVAL

Returns the current sequence value.

CYCLE/NOCYCLE

Specifies whether the sequence continues to generate values after reaching its maximum or minimum values.

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Data

A collection of facts from which conclusions may be drawn. Numbers, characters, images, or other method of recording, in a form that can be assessed by a human or (especially) input into a computer, stored and processed there, or transmitted on some digital channel.

Data control language (DCL)

Manages the changes made by DML statements; changes to the data can be grouped together into logical transactions.

Data definition language (DDL)

Set-up, change and remove data structures from tables.

Data dictionary

Created and maintained by the Oracle Server and contains information about the database.

Data integrity

The state or quality of the data in the database as being entire or complete, honest, and correct. Data integrity rules ensure that users perform only operations which leave the database in a correct, consistent state.

Data manipulation language (DML)-

Enters new rows, changes existing rows, and removes unwanted rows from tables in the database.

Data model

The product of the database design process which aims to identify and organize the required data. A data model says what information is to be contained in a database, how the information will be used, and how the items in the database will be related to each other. One of the most widely used methods for developing data models is the entity-relationship model.

Data security

Covers access and use of the database objects and the actions that those users can have on the objects.

Data structure

A physical method of organizing a collection of data in a database to allow it to be manipulated effectively. Examples of data structures are: table, index, view.

Data type

A classification identifying one of various types of data, stating the possible values for that type, the operations that can be done on that type, and the way the values of that type are stored.

Data type conversion

To convert data of one data type to a different data type.

Data warehouse

A generic term for a system for storing, retrieving and managing large amounts of any type of data.

Database

A collection of data arranged for ease and speed of search and retrieval. One or more large structured sets of persistent data, usually associated with software to update and query the data.

Database link connections

Allows local users to access data on a remote database.

Database objects

A data structure in the database.

Database transaction

A database transaction consists of one of the following: DML statements which constitute one consistent change to the data;one DDL statement; one DCL statement

DATE data type

Date and time value between January 1, 4712 B.C. and A.D. December 31, 9999.

DATE functions

Functions that return a value of DATE data type or a numeric value.

DBMS

Database Management System; stores, retrieves, and modifies data in the database on request.

DCL

Data Control Language; gives or removes access rights to both the Oracle database and the structures within it.

DD date format

Numeric day of the month.

DDL

Data Definition Language; setup, change, and remove data structures from tables.

Deceased

Dead, no longer living.

Decline

Deteriorate, to move downward.

DECODE

Implements conditional processing (IF-THEN-ELSE logic) within a SQL statement; it is specific to the Oracle syntax.

Default

A particular setting or value for a variable that is assigned automatically by an operating system and remains in effect unless canceled or overridden by the operator, or specifies a preset value if a value is omitted in the INSERT statement.

Deferred

Put off, delay.

Degree

A property of an end of a relationship between X and Y, that describes how many of X is related to Y. Both ends of a relationship must have a defined degree. Same as cardinality.

DELETE

Removes existing rows from a table.

Demographics

The characteristics of human populations and population segments.

Depreciation

A decrease or loss in value, because of age, wear, or market conditions.

Deregulation

To free from restriction, especially to remove government regulations from (example: deregulate the airline industry).

Descending/DESC

Orders the rows in descending order; Z A.

DESCRIBE (DESC)

An iSQL*Plus command to display the structure of a table.

DISABLE CONSTRAINT

To deactivate an integrity constraint.

Discrete

Defined for a finite or countable set of values; not continuous.

Discriminator column

A column that is created in the single table implementation of the supertype, to hold values that distinguish between the subtypes.

Disk I/O

Writing and reading of data onto and from a storage disk.

DISTINCT

A command that suppresses duplicates, or makes the function consider only non-duplicate values within a column.

Distribution

The commercial activity of transporting and selling goods from a producer to a consumer.

Diversify

To give variety to; vary (example: diversify a menu.) To spread out activities or investments, especially in business.

DML

Data Manipulation Language; enters new rows, changes existing rows, and removes unwanted rows from the tables in the database.

Domain

Set of all possible values of an independent variable of a function.

DROP COLUMN

To delete a column from a table.

DROP CONSTRAINT

Removes a constraint from a table.

DROP INDEX

Removes an index.

DROP SEQUENCE

Removes a sequence.

DROP SYNONYM-

Removes a synonym.

DROP TABLE

Removes the definition of a table.

DROP VIEW

Removes a view.

DUAL Table

Dummy table used to view results from functions and calculations.

Dummy

A piece of information entered into a computer only to meet prescribed conditions and having no effect on operations.

DY date format

Name of the day; three-letter abbreviation.

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Efficiency

Skillfulness in avoiding wasted time and effort.

Embedded

To enclose snugly or firmly.

ENABLE CONSTRAINT

To activate an integrity constraint currently disabled.

Entity

A named thing or category of things that is significant to the business and about which data must be known.

Entity relationship diagram

A drawing that is used to represent a data model.

Entity relationship modeling

The practice of creating data models and using entity-relationship diagrams to represent the data requirements of a business.

Equality

A statement, usually a condition, that one thing equals another.

Equijoin

Values in a column in one table must be equal to a value in another table; also called an inner join or simple join.

ERDish

The language or statements used to describe relationships between entities in an entity-relationship diagram.

ESCAPE

This option identifies the escape characters; which causes the server to interpret the character literally. 

Exclusive

Not including the specified limits, but only the area between them: 20-25, exclusive; that is, 21, 22, 23 and 24.

Exclusive OR relationship

A logical operator that returns a true value if one, but not both, of its operands is true. Also called XOR.  `A xor B' means `A or B, but not both'. (example: "I want to get cherry pie xor a banana split.")

Exhaustive

Treating all parts or aspects without omission.

Expenditure

That which is paid out; an expense.

Explicit

Fully and clearly expressed; leaving nothing implied.

Expression

A symbol or combination of symbols that represents a quantity or a relationship between quantities.

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Feedback

The return of information about the result of a process or activity; an evaluative response.

Field

Intersection of a row and column.

Finance

The management of money, banking, investments, and credit.

First Normal Form (1NF)

The output of the first step of database normalization.  First Normal Form eliminates repeating groups by putting each into a separate table and connecting them with a one-to-many relationship.

fm

‘format-model’; used to remove padded blanks or to suppress leading zeros.

FORCE

Creates a view regardless of whether or not the base tables exist.

Foreign key

A column or set of columns that defines how tables relate to each other; this column or set of columns refers to a

in the same table or another table, or Referential Integrity Constraint, designates a column or combination of columns (child table) as the column(s) that establishes a relationship between a primary key or a unique key in the same table and a different table (parent table).

Format

The arrangement of data for storage or display.  

Formulate

To state as or reduce to a formula.  To express in systematic terms or concepts.  To devise or invent (example: formulate strategy.)

FROM

The clause that specifies the table containing the columns.

FULL OUTER JOIN

Performs a join on two tables, retrieves all the rows in the Left table, even if there is no match in the Right table.  It also retrieves all the rows in the Right table, even if there is no match in the Left table.  The WHERE clause lists the Left and Right tables.

Function-based

Index based on expressions.

Functional resume

A document highlighting an individual's accomplishments and job experience, organized into sections that focus on areas of skill and achievement, rather than according to chronological date.

Functions

Are used to perform calculations on data, modify individual data items, manipulate output for groups of rows, format dates and numbers for display, convert column data types.

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Generic

Relating to or descriptive of an entire group or class; general.

Globalization

Describes how a system or occurrence (business, organization, popular culture) becomes worldwide in scope and application.

GRANT privilege

The right to grant specific system privileges to a user.

Graphical user interface (GUI)

An interface for issuing commands to a computer utilizing a pointing device, such as a mouse, that manipulates and activates graphical images on a monitor.

Grid computing

An ambitious and exciting global effort to develop an environment in which individual users can access computers, databases and experimental facilities simply and transparently, without having to consider where those facilities are located.

GROUP BY clause

Divides the rows in a table into groups.

Group functions

Operate on sets of rows to give one result per group.

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HAVING clause

Is used to specify which groups are to be displayed; restricts groups that do not meet group criteria.

Hardware

A computer and the associated physical equipment directly involved in the performance of data-processing or communications functions.  Machines and other physical equipment directly involved in performing an industrial, technological, or military function.

Hierarchical relationships

A series of relationships that reflect entities organized into successive levels. 

High-volume entity

An entity that will have a large number of instances.

Historical data

Data that records changes over time.

Hone

To sharpen. To perfect or make more intense or effective.

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IF-THEN-ELSE

A programming IF statement that checks condition(s), if the condition(s) is true the THEN statement(s) get accomplished; if the condition is false the ELSE statement(s) gets accomplished.

Implementation-free

Not dependent on the physical model.

Implicit

Implied or understood though not directly expressed.

IN

Tests for values in a specified list of values.

IN operator

Compares if value is in the list of all values returned by the subquery. 

Inapplicable

Incapable of being applied.

Inclusive

Including the specified limits and the area between them: the numbers one to ten, inclusive.

INCREMENT BY

Specifies the interval between sequence numbers.

Index

Improves the performance of some queries; it is a schema object that speeds up retrieval of rows.

Inequality

A condition/relation showing that a quantity is greater than or less than another quantity.

Information

Knowledge, intelligence, a particular piece of data with a special meaning or function. Information is often the result of combining, comparing, and performing calculations on data. 

Infrastructure

The basic framework or features of a system. The basic facilities, services, and installations needed for the functioning of a community or society, such as transportation and communications systems, water and power lines, and public institutions including schools, post offices, and prisons.

INITCAP

Converts alpha character values to uppercase for the first letter of each word, all other letters in lowercase.

INLINE VIEW

Subqueries with an alias that can be used within a SQL statement

Inner Join

is a join of two tables returning only matched rows

Inner Query

Also called the subquery, returns a value that is used by the outer query.

Input

Raw data entered into the computer

INSERT INTO

Adds a new row to a table

Instance

An occurrence or example.

INSTR

Returns the numeric position of a named string.

Integration

Combining software or hardware components or both into an overall system.

Integrity Constraint

Ensure that the data adheres to a predefined set of rules.

Interface

(a)The point of interaction or communication between a computer and any other entity, such as a printer or human operator.

(b) The layout of an application's graphic or textual controls in conjunction with the way the application responds to user activity: an interface whose icons were hard to remember.

Intersection Entity

The product of the resolution of a many to many relationship.

INTERVAL DAY TO SECOND

Allows time to be stored as an interval of days to hours, minutes, and seconds.

INTERVAL YEAR TO MONTH

Allows time to be stored as an interval of years and months.

IS NULL

Condition tests for null values.

ISO

International Organization for Standardization, Geneva; an organization that sets international standards. ISO deals with all fields except electrical and electronics.

Iteration

Repetition.

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Join(s)

Display data from two or more related tables.

Joining

The capability in SQL to bring together data that is stored in different tables.

Journalling

Keeping an on-going record of transactions.

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Keyword

Refers to an individual SQL element.

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LAST_DAY

Function that calculates the last day of the month specified.

LEFT OUTER JOIN

Performs a join on two tables, retrieves all the rows in the Left table even if there is no match in the Right table.  The WHERE clause lists the Left and Right tables.

LENGTH

Returns the number of characters in the expression.

LIKE

Selects rows that match a character pattern.

Literal

A character, a number, or a date value.

LOB

Large object data type to store large and unstructured data.

Lock

Mechanisms that prevent destructive interaction between transactions accessing the same resource

Logging

Keeping an on-going record of transactions.

Logical conditions

Combine the results of two component conditions to produce a single result based on them or inverts the result of a single condition.

Logical operators

AND, OR, NOT.

Logistics

The planning, execution and control of the movement and placement of people and/or goods, and of the supporting activities related to such movement and placement within a system organized to achieve specific objectives.

LONG

Variable-length character data up to 2 gigabytes.

LOWER

Converts alpha character values to lowercase.

LPAD

Pads the character value right-justified to a total width of a specified character positions.

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Mandatory

Required, necessary, imperative.

Manipulation

To move, arrange, operate, or control in a skillful manner.

Many-to-many (M:M)

A type of relationship that has "one or more" cardinality at both ends. A relationship in which many records in one table match many records in another table.

Map

A representation. To map the conceptual model to a relational design is to represent the elements of an ERD (entities, attributes, relationships) with database elements (tables, attributes, foreign keys).

Matrix diagram

A grid-like drawing that can be used to discover and record relationships between entities in an entity-relationship model.

MAX

Returns maximum value ignoring nulls.

MAXVALUE/NOMAXVALUE

Specifies a maximum or default value the sequence can generate.

MERGE INTO

Provides the ability to conditionally update or insert data into a database table.

MIN

Returns minimum value ignoring nulls.

MINVALUE/NOMINVALUE

Specifies the minimum sequence or default value.

MOD function

Returns the remainder of a division.

Modification

Change, revision.

MONTHS_BETWEEN

Function that calculates the number of months between two dates

Multiple-row functions

These functions can manipulate groups of rows to give one result per group of rows.

Multiple-row operators

Operator that expects one or more values.

Mutually exclusive

A relationship that presents choices which are unable to be true at the same time. A choice between mutually exclusive possibilities means selecting "either this or that."

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NATURAL JOIN

Joins two tables based on the same column name

Nesting functions

Is using a function call as an argument to another function.

NEXT_DAY

Function that calculates the next date of the day specified

NEXTVAL

Returns the next available sequence value.

NO FORCE

Creates a view only if the base tables exist.

Nontangible

Incapable of being perceived by the senses.  Same as intangible.

Nontransferability

Property of a relationship where an instance of A is related to an instance of B, and the association cannot be moved to another instance of B.  This is normally determined by the business rules.

Nonequijoin

A join condition containing something other than an equality operator; values in a column in one table must be conditional to but not equal to a value(s) in another table.

Normalization

A series of steps followed to obtain a database design that allows for efficient access and storage of data in a relational database. These steps reduce data redundancy and the chances of data becoming inconsistent.

NOT-

Inverts the value of the condition

NOT NULL

Constraint ensures that the column contains no null values.

NULL

A value that is unavailable, unassigned, unknown, or inapplicable; it is not a zero or space.

NULLIF compares two expressions; if they are equal, the function returns null; if they are not equal, the function returns the first expression.

NUMBER(size)

A data type that is commonly used for numbers.  (Size) refers to the maximum number of digits.

NUMBER data type

Number value; only contains a number, plus or minus sign, and a decimal point.

Number functions

These functions accept numeric input and return numeric values.

Numeric data type

Number value; only contains a number, plus or minus sign, and a decimal point.

NVL

Converts nulls to an actual value, or to force group functions to include null values.

NVL2

Examines the first expression; if the first expression is not null, it returns the second expression; if the first expression is null, it returns the third expression.

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Object

A data structure in a database.

Object privileges

The right to manipulate the content of the objects in the database.

Obsolete

 No longer in use, outdated.

OLTP

Online transaction processing.

ON Clause-

Allows a natural join based on an arbitrary condition or to specify columns to join; separates the join condition from other search conditions

ON DELETE CASCADE

Deletes the dependent rows in the child table when a row in the parent table is deleted.

ON DELETE SET NULL

Converts dependent foreign key values to null.

One-to-one (1:1)

A type of relationship that has "one and only one" cardinality at both ends. A relationship where each record in Table A can be related to one, and only one, record in Table B, and vice versa.

Operating system

Software designed to control the hardware of a specific data-processing system in order to allow users and application programs to make use of it.

Operator precedence

An order of rank relating to SQL commands and operations, or rules that determine the order expressions are evaluated and calculated.

Optional

Not required; left to choice.

Optionality

A property of an end of a relationship between X and Y,  that describes whether X must be or may be related to Y.  Both ends of a relationship must have a defined optionality.

OR

Either condition can be true for a record to be selected.

Oracle 9i /10g

A comprehensive high-performance infra-structure for e-business which includes everything needed to develop, deploy, and manage Internet applications.

Oracle HTML DB

A component in the Oracle Database 10g. HTML DB is a browser based Web application development tool for the Oracle database.

Oracle instance

A combination of the background processes and memory buffers.

ORDBMS

Object Relational Database Management System; defines data types and objects and is fully compatible with relational databases and supports multimedia and large objects.

ORDER BY-

Clause used to sort rows.

Order of operations-

The prescribed procedure of mathematical operations

Outer join (+)

Returns rows that do not meet the join condition along with rows that do meet the join condition.

Outer query

Also called the main query, accepts a value from the inner query to solve its original query.

Output

Data that is processed into information.

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Parallel operations

The simultaneous execution of 2 different operations. In the system development lifecycle, it refers to the simultaneous use of the old and the new systems. It is usually done prior to making the old obsolete and fully replacing it with the new.

Parent record

The record that holds the column data that references other tables.

Personal inventory

A detailed, itemized record of accomplishments. 

Perspective

Point of view.

Petabyte

A unit of computer memory or data storage capacity equal to 1,024 terabytes (250 bytes). One quadrillion bytes.

Physical

Of or relating to material things: our physical environment.

Physical model

A design for an object (a car, a house, a database, etc.) which includes implementation details such as size, volume, weight, etc.)

Platform

The basic technology of a computer system's hardware and software that defines how a computer is operated and determines what other kinds of software can be used.

Pointer

A variable that holds the address of a core storage location,

Populate

To supply with inhabitants.  To populate a table is to enter data into it.

Portal

An entrance or a means of entrance

Primary key

A constraint which ensures that the column contains no null values and uniquely identifies each row of the table, or unique identifier of each row of data in a table; it must contain a value and it must be unique. The set of mandatory columns within a table that is used to enforce uniqueness of rows, and that is normally the most frequent means by which rows are accessed.

Primary UID

The designated unique identifier for an entity, when there is more than one UID available.

Privilege

The right to execute particular SQL statements.

Procedural business rule

A business rule that is workflow or business process related. (example: A has to happen before B, and then C has to happen at the same time as D.) This is also called a process business rule.

Procurement

To get by special effort; obtain or acquire. All of the processes involved in requesting, ordering, auditing, and paying for goods and services. 

Projection

The capability in SQL to choose the columns in a table that you want returned from a query.

Property

A characteristic.

Proprietary

Owned by a private individual or corporation under a trademark or patent.

Pseudocolumn

Behaves like a table column but is not actually stored in the table, or dummy column, are not actual columns in a table but they behave like columns.

PUBLIC privilege

The right of an owner of a table to grant access to all users.

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Query

A question to be answered or solved.

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RAW & LONG RAW

Raw binary data.

Read consistency

An automatic implementation that guarantees a consistent view of the data at all times. Changes made by one user do not conflict with changes made by another user.

Readability

Code that can be easily read

Recursive relationship

A relationship between an entity and itself.

Redundancy

Something that is unnecessarily repetitive, the state of being unnecessarily repetitive.

Redundant

Unnecessarily repetitive.

REFERENCES

Identifies that table and column in the parent table.

Relational database

Collections of objects or relations, set of operators to act on those relations, and data integrity for accuracy and consistency.

Relationship

A connection or association between objects.

RENAME

Used to change the name of a table.

REPLACE

Searches a text expression for a character string and, if found, replaces it with a specified replacement string.

Report generation

The process of generating reports.

Reserved word

Words that have a special meaning and function within a computer system or language.

Résumé

A brief account of one's work experience and qualifications, often submitted with an employment application.

Revenue

Income. That which returns or comes back from an investment.

REVOKE privilege

The right to take away privileges granted to other users.

RIGHT OUTER JOIN

Performs a join on two tables, retrieves all the rows in the Right table even if there is no match in the Left table.  The WHERE clause lists the Left and Right tables.

Robust

Powerfully built; sturdy.

Role

A named group of related privileges that can be granted to the user.

ROLLBACK

Ends the current transaction by discarding all pending data changes

ROLLBACK TO SAVEPOINT

Rolls back the current transaction to the specified savepoint, thereby discarding any changes and or savepoints created after the savepoint to which you are rolling back.

ROUND

Rounds the column, expression, or value to a set number of decimal places.

Row

Represents all data required for an instance. An entry in a table, consisting of values for each appropriate column.

ROWID

Hexadecimal string representing the unique address of a row in its table.

ROWNUM

A pseudocolumn which assigns a sequential value starting with 1 to each of the rows returned from the subquery.

RPAD

Pads the character value left-justified to a total width of a specified character positions.

RR date format

Century value depends on the specified year and the last two digits of the current year.

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SAVEPOINT

Marks a savepoint within the current transaction

Scalability

The ease with which a system or component can be modified to fit the problem area.

Schema

A collection of objects that are the logical structures that directly refers to the data in the database.

Scheme

A chart, diagram, or outline of a system or object.

Script files

Saved SQL statements.

Second Normal Form (2NF)

The output of the second step of database normalization. Second Normal Form eliminates functional dependencies on a partial key by putting the fields in a separate table from those that are dependent on the whole key.

Secondary UID

An alternate unique identifier for an entity, when there is more than one UID available.

Security

The protection of data against unauthorized access.

SELECT

Statement used to extract data from the database using SQL.

Selection

The capability in SQL to choose the rows in a table returned from a query.

Self Join

Joins a table to itself.

Semi-colon(;) and forward slash (/)

Markers for the end of the statement.

Sequences

Generates a numeric value.

SET UNUSED

Marks one or more columns as unused so that they can be dropped when the demand on system resources is lower.

SGA

System Global Area; an area of memory used for the database information shared by the Users.

Sharable

An object that can be shared by multiple users.

Simple UID

A unique identifier that is composed of one attribute.

Simple view

Derives data from a table, no functions or groups, performs DML operations through the view.

Single-row functions

These functions operate on single rows only and return one result per row.

Single-row subquery

Returns only one row from the inner SELECT statement.

Softbox

A four-sided visual element with rounded corners. This is used to represent an entity in an entity-relationship diagram.

Software

The programs, routines, and symbolic languages that control the functioning of the hardware and direct its operation.

Sort

To arrange according to class, kind, or size.

Source document

Written or printed material that is used and/or produced by the business and which analysts can use to determine information requirements.

SQL

Structured Query Language, an industry-standard language for creating, updating and, querying relational database management systems.

Stakeholder

One who has a share or an interest, as in a business enterprise or project.

START WITH

Specifies the first sequence number to be generated.

Statement

Is a combination of two or more clauses.

STDDEV

Calculates standard deviation ignoring null values.

Stellar

Outstanding.

String

A group of character data.

Structural business rule

A structural business rule indicates the types of information to be stored and how the information elements interrelate.

Subentity

Synonymous with subtype.  A type of entity.  An entity may be split into two or more subentities, each of which has common attributes and/or relationships.  Subentities may have attributes and/or relationships of their own and may be further subtyped to lower levels.

Subquery

Is a SELECT statement that is embedded in a clause of another SELECT statement.

Subset

A set whose members are members of another set; a set contained within another set.

SUBSTR

Returns specified characters from character value starting at a specified character position and going specified character positions long.

Subtype

Synonymous with subentity. A type of entity. An entity may be split into two or more subtypes, each of which has common attributes and/or relationships. Subtypes may have attributes and/or relationships of their own and may be further subtyped to lower levels.

SUM

Calculates the sum ignoring null values.

Supernatural

Of or relating to existence outside the natural world. Of or relating to the miraculous.

Synonym

An expression that serves as a figurative or symbolic substitute for another, or gives alternative names to objects.

Supertype

A means of classifying an entity that has subtypes.

Syntax

The rules governing the formation of statements in a programming language.

SYSDATE

A function that returns the current database server date and time.

System crash

A sudden failure of a program or operating system, usually without serious consequences.

System development life cycle (SDLC)

The overall process of developing information systems through a multi-step process from investigation of initial requirements through analysis, design, implementation and maintenance. There are many different models and methodologies, but each generally consists of a series of defined steps or stages.

System privileges

The right to access the database and its objects.

System security

Covers access and use of the database at the system level.

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Table

An orderly arrangement of data, especially one in which the data are arranged in columns and rows in an essentially rectangular form, or stores data, basic unit of storage, composed of rows and columns. It is often an implementation of an entity.

Table level constraint

References one or more columns and is defined separately from the definitions of the columns in the table.

Tangible

Perceptible by the senses especially the sense of touch.

Terabytes

A unit of computer memory or data storage capacity equal to 1,024 gigabytes (240 bytes).  One trillion bytes.

Theoretical

Restricted to theory; not physical.

Third Normal Form (3NF)

The output of the third step of database normalization. Third Normal Form eliminates functional dependencies on non-key fields by putting them in a separate table. At this stage, all non-key fields are dependent on the key, the whole key and nothing but the key.

Time-related constraint

A constraint or data restriction that results from the time dimension.

TIMESTAMP

Allows the time to be stored as a date with fractional seconds.

TO_CHAR function

Converts dates or numbers to character strings with optional formatting.

TO_DATE function

Converts a character string representing a date to a date value with optional formatting.

TO_NUMBER function

Converts a character string containing digits to a number with optional formatting.

TOP-n analysis

Asks for the N largest or smallest values in a column.

Totem

An animal, plant, or natural object serving among certain tribal or traditional peoples as the emblem of a clan or family and sometimes revered as its founder, ancestor, or guardian. A representation of such an object.

Transaction

Consists of a collection of DML statements that form a logical unit of work.

Transferable

Property of a relationship between A and B,  where an instance of A is related to an instance of B, and the association can be moved to another instance of B. This is normally determined by the business rules.

Transform

To change. To transform the conceptual model to a relational design is to exchange the elements of an ERD (entities, attributes, relationships) with database elements (tables, attributes, foreign keys).

Transitive dependency

A condition that exists when any attribute in an entity is dependent upon any other non-UID attribute in that entity. This is a violation of third normal form.

TRIM

Enables you to remove heading or trailing characters (or both) from a character string.

TRUNC

Truncates the column, expression, or value to a set number of decimal places.

TRUNCATE TABLE

Used to remove all rows from a table and to release the storage spaced used by the table.

Tuple

Row; record.

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Unique identifier (UID)

Any combination of attributes and/or relationships that serves, in all cases, to uniquely identify an occurrence of an entity.

Unique key

An integrity constraint that requires every value in a column or set of columns be unique. A set of columns within a table that is used to enforce uniqueness of rows, and that is an alternate means by which rows are accessed.

UPDATE

Modifies existing rows in a table.

UPPER

Converts alpha character values to uppercase.

URL

Uniform resource locator, an Internet address usually consisting of the access protocol (http), the domain name (www.hmco.com), and optionally the path to a file or resource residing on that server (trade).

USER

Someone doing "real work" with the computer, using it as a means rather than an end.

User acceptance testing (UAT)

The type of testing where monitored users determine whether a system meets all their requirements, and will support the business for which it was designed.

User table

Tables created by the user.

USING clause

Performs an equijoin based on the same specified column name.

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VARCHAR2(size)

An Oracle Corporation datatype. (Size) refers to the maximum number of characters. Specifically, it is a variable-length, alpha-numeric string with a maximum length of 4000 bytes. If data entered for a column of type VARCHAR2 is less than 4000 bytes, no spaces will be padded; the data is stored with a length as entered. If data entered is more than 4000 bytes, an error occurs.

It differs from char in that it makes more efficient use of physical storage inside the database.  Space is allocated for the actual number characters, as opposed to the maximum specified by (size).

VARCHAR2 data type

Stores variable-length strings.

Variable

A quantity capable of assuming any of a set of values.  A symbol representing such a quantity.

VARIANCE

Calculates the variance ignoring null values.

Venn diagram

A diagram using circles to represent sets, with the position and overlap of the circles indicating the relationships between the sets.

Venture capitalist (VC)

A speculator who makes money available for innovative projects (especially in high technology.)

View

A table of logical subsets or combinations of data based on a table or another view.

Volatile

Tending to vary often or widely, highly changeable.

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WHERE clause

Restricts the rows returned by a select statement.

White space

Space on a page or poster not covered by print or graphic matter.

Wildcard

A symbol that stands for one unspecified character, used especially in searching text.  The percentage sign (%) and the underscore (_) are SQL wildcards.

WITH CHECK OPTION-

Prohibits changing rows that are not in the subquery, or specifies that INSERTS and UPDATES performed through the view can't create rows which the view cannot select.

WITH GRANT OPTION

Allows the grantee to grant the object privileges to other users and roles.

WITH READ ONLY

Ensures that no DML operations can occur.

WW date format

Numeric week of the year.

X Y Z

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YYYY date format

Full year in numbers.