GLOSSARY OF DATA MANAGEMENT TERMS
This glossary is a collection of definitions of commonly used data management terms.
Access Control
The ability to manage which users or groups of users have the privilege to create, read, update or delete data that is held in a database.
Attribute
Any detail that serves to qualify, identify, classify, quantify or express the state of a relation or an entity.
Boyce–Codd Normal Form (BCNF)
In relational data analysis, a relation is in Boyce–Codd normal form if every determinant is a candidate key.
CASE
Acronym for Computer Aided Software Engineering – a combination of software tools that assist computer development staff to engineer and maintain software systems, normally within the framework of a structured method.
Column
The logical structure within a table of a relational database management system (RDBMS) that corresponds to the attribute in the relational model of data.
Conceptual data model
A detailed model that captures the overall structure of organisational data while being independent of any database management system or other implementation consideration – it is normally represented using entities, relationships and attributes with additional business rules and constraints that define how the data is to be used.
Corporate data model
A conceptual data model whose scope extends beyond one application system.
Data
A re-interpretable representation of information in a formalised manner suitable for communication, interpretation or processing.
Data administration
A role in data management concerned with mechanisms for the definition, quality control and accessibility of an organisation’s data.
Data dictionary
Software in which metadata is stored, manipulated and defined – a data dictionary is normally associated with a tool used to support software engineering.
Data management
A corporate service which helps with the provision of information services by controlling or co-ordinating the definitions and usage of reliable and relevant data.
Data mining
The process of finding significant, previously unknown, and potentially valuable knowledge hidden in data.
Data model
(i) An abstract, self-contained logical definition of the data structures and associated operators that make up the abstract machine with which users interact (such as the relational model of data). (ii) A model of the persistent data of some enterprise (such as an entity– relationship model of data required to support a human resources department).
Data modelling
The task of developing a data model that represents the persistent data of some enterprise.
Data owner
(i) The owner of a data definition is the person in the organisation who has the authority to say that this data should be held and that this definition is the appropriate definition for the data. (ii) The owner of a data value is the person or organisation that has authority to change that value.
Data profiling
A set of techniques for searching through data looking for potential errors and anomalies, such as similar data with different spellings, data outside boundaries and missing values.
Data quality
The state of completeness, validity, consistency, timeliness and accuracy that makes data appropriate for a specific use.
Data recovery
Restoring a database to a state that is known to be correct after a failure.
Data security
Protecting the database against unauthorised users.
Data steward
The person who maintains a data definition on behalf of the owner of the data definition.
Data warehouse
A specialised database containing consolidated historical data drawn from a number of existing databases to support strategic decision making.
Database
(i) An organised way of keeping records in a computer system. (ii) A collection of data files under the control of a database management system.
Database administration
A role in data management concerned with the management and control of the software used to access physical data.
Database management system (DBMS)
A software application that is used to create, maintain and provide controlled access to databases.
Datatype
A constraint on a data value that specifies its intrinsic nature, such as numeric, alphanumeric, date.
Discretionary access control (DAC)
Access control where the users who are granted access rights are allowed to propagate those rights to other users.
Domain
A pool of values from which an attribute must take its value – a domain provides a set of business validation rules, format constraints and other properties for one or more attributes that may exist as a list of specific values, as a range of values, as a set of qualifications, or any combination of these.
Enterprise architecture
A process of understanding the different elements that make up the enterprise, such as the people, the information, the processes and the communications, and how those elements interrelate.
Enterprise resource planning (ERP) software
A software package that provides a single integrated database that is planned to meet an organisation’s entire data needs for the management of its resources.
Entity
In a conceptual data model, a named thing of significance about which information needs to be held in support of business operations.
First normal form (1NF)
In relational data analysis, a relation is in first normal form if all the values taken by the attributes of that relation are atomic or scalar values – the attributes are single-valued or, alternatively, there are no repeating groups of attributes.
Foreign key
One or more attributes in a relation (or columns in a table) that implement a many-to-one relationship that the relation (or table) has with another relation (or table) or with itself.
HTML
Acronym for HyperText Markup Language – the markup language used to convey the way that a document is presented by a web browser.
IEC
Acronym for the International Electrotechnical Commission – collaborates with ISO in the development of international standards for information systems.
Information
(i) Something communicated to a person. (ii) Knowledge concerning objects, such as facts, events, things, processes, or ideas, including concepts, that have a particular meaning within a certain context.
Information management
The function of managing information as an enterprise resource, including planning, organising and staffing, and leading, directing, and controlling information.
Information resource management
The concept that information is a major corporate resource and must be managed using the same basic principles used to manage other assets.
Information system
A collection of manual and automated components that manages a specific information resource.
ISO
Acronym for the International Organization for Standardization – collaborates with IEC in the development of international standards for information systems.
Mandatory access control (MAC)
Access control where access rights cannot be changed by the users.
Metadata
Data about data – that is, data describing the structure, content or use of some other data.
Multi-level security
The ability of a computer system to process information with different security levels, to permit access by users with different security clearances, and to prevent users from obtaining access to information for which they do not have authorised access.
Multimedia data
Data representing documents, audio (sound), still images (pictures) and moving images (video).
Normal form
A state of a relation that can be determined by applying simple rules regarding dependencies to that relation.
Normalisation
Another name for relational data analysis.
Object orientation
A software-development strategy based on the concept that systems should be built from a collection of reusable components called objects that encompass both data and functionality.
ODMG
Acronym for the Object Data Management Group, a body that has produced a specification for object-oriented databases.
OLAP
Acronym for online analytical processing – a set of techniques that can be applied to data to support strategic decision making.
OLTP
Acronym for online transactional processing – data processing that supports operational procedures.
Primary key
The set of mandatory attributes in a relation (or mandatory columns in a table) that is used to enforce uniqueness of tuples (or rows).
RDBMS
Acronym for relational database management system – a database management system whose logical constructs are derived from the relational model of data. Most relational database management systems available are based on the SQL database language and have the table as their principal logical construct.
Relation
The basic structure in the relational model of data – formally a set of tuples, but informally visualised as a table with rows and columns.
Relational data analysis
A technique of transforming complex data structures into simple, stable data structures that obey the rules of relational data design, leading to increased flexibility and reduced data duplication and redundancy – also known as normalisation.
Relational model of data
A model of data that has the relation as its main logical construct.
Relationship
In a conceptual data model, an association between two entities, or between one entity and itself.
Repository
Software in which metadata is stored, manipulated and defined – a repository is normally associated with a corporate data management initiative.
Schema
A description of the overall logical structure of a database expressed in a data definition language (such as the data definition component of SQL).
Second normal form (2NF)
In relational data analysis, a relation is in second normal form if it is in first normal form and every non-key attribute is fully functionally dependent on the primary key – there are no part-key dependencies.
SQL
Originally, SQL stood for structured query language. Now, the letters SQL have no meaning attributed to them. SQL is the database language defined in the ISO/IEC 9075 set of international standards, the latest edition of which was published in 2003. The language contains the constructs necessary for data definition, data querying and data manipulation. Most vendors of relational database management systems use a version of SQL that approximates to that specified in the standards.
Structured data
Data that has enforced composition to specified datatypes and relationships and is managed by technology that allows for querying and reporting.
Table
The logical structure used by a relational database management system (RDBMS) that corresponds to the relation in the relational model of data – the table is the main structure in SQL.
Third normal form (3NF)
In relational data analysis, a relation is in third normal form if it is in second normal form and no transitive dependencies exist.
Tuple
In the relational model of data, the construct that is equivalent to a row in a table – it contains all the attribute values for each instance represented by the relation.
Unified Modeling Language (UML)
A set of diagramming notations for systems analysis and design based on object oriented concepts.
Unstructured data
Computerised information which does not have a data structure that is easily readable by a machine, including audio, video and unstructured text such as the body of a word-processed document – effectively this is the same as multimedia data.
XML
Acronym for eXtensible Markup Language – the markup language used to convey the definition, structure and meaning of the information contained in a document.
