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Group: database model
topics >
computer science >
database agents
Topic:
database as a model of reality
Topic:
database entities
Topic:
database keys and indexing
Topic:
database record
Topic:
database schema
Topic:
entity-relationship database model
Topic:
existence of database entities
Topic:
fact-based analysis for database design
Topic:
fundamental concepts such as type, attributes, relationships are all the same
Topic:
heterogeneous database
Topic:
loosely structured data
Topic:
network and hierarchical databases
Topic:
relational database
Topic:
uniform data model
data type
Group:
program design
Group:
hypertext
Group:
information
Group:
natural language
Group:
relationship information
Topic:
classification
Topic:
collection class
Topic:
data as a named set of data objects
Topic:
database implementation
Topic:
design for change
Topic:
models of parallel computation
Topic:
object-oriented databases
Topic:
object-oriented design
Topic:
object-oriented modelling language
Topic:
problem of classifying information
Topic:
Thesa data model
Summary
There are three broad choices for a data model. It can be a detailed model of reality with internal objects corresponding to external entities. It can consists of a well-defined data language from which a data schema is constructed. It can be a uniform model based on a simple concept. Perhaps these choices arise from different ways of viewing the world.The existing models are structured around the data record. They are either highly structured or unstructured. This makes them a poor model for reality. Hypertext may be an intermediate model.
Kent distinguishes simple objects from symbols, relationships, and executables.
(cbb 1/90)
Subtopic: database independent of applications
Quote: different data models probably arise from different ways of perceiving information [»kentW_1978] Quote: programming, writing documentation, and building databases are all for producing a large, complex document [»mashJR_1976a]
Subtopic: data as relational
Quote: explicitly represent and enforce all database issues of concern to the user community; not hidden in applications [»coddEF_1990] Quote: the results of a database command must be independent of the database organization and access methods [»coddEF_1990] Quote: cursors are not required within a database; can lead to severe bugs; e.g., CODASYL [»coddEF_1990]
Subtopic: business information
Quote: fundamental laws of the relational model apply to all database management systems [»coddEF_1990] Quote: use second and third normal form to avoid insertion, update and deletion dependencies; reduce need for restructuring; uniform query statistics [»coddEF5_1971]
Subtopic: separate persistence, sharing, structure
Quote: in data retrieval, queries and data descriptions are fairly precise; simple matching is sufficient [»blaiDC1_1996] Quote: business data uses indexed sequential files for sequential processing and indexed retrieval; also relational and object-oriented databases [»glasRL9_1997]
Subtopic: data as collections
Quote: a data model should treat persistence, sharing and structure independently [»balzRM_1986]
Subtopic: higher-order structures
Quote: the Integrated Data Store moves list processing to disk with circular chains of links from master records; maybe basis for information algebra [»bachCW_1964] Quote: data description does not support collections of data; hard to change without impacting applications [»coddEF6_1970]
Subtopic: data as value, symbol, relation, function
Quote: the molecular semantics for a database searches for meaningful units larger than n-ary relationships [»coddEF12_1979]
Subtopic: data record
Quote: objects are simple, symbols, relationships, or executables [»kentW_1978] Quote: Pegasus data model contains types, objects and functions; like Iris [»ahmeR12_1991] Quote: a computation system contains tokens that are occurrences of symbols outside the system; equivalent if symbols equivalent [»kentW6_1991]
Subtopic: database performance
Quote: hierarchical, relational, and network models are variations of the data record model [»kentW_1978] Quote: databases have either well-defined record structures, or unstructured text files [»akscRM5_1984] Quote: the atomic semantics for a database searches for meaningful units that are as small as possible
Subtopic: independent databases
Quote: allow online addition and removal of performance-oriented structures for databases; do not stop the database [»coddEF_1990] Quote: performance-oriented structures should be independent of semantic information in the database and catalog [»coddEF_1990]
Subtopic: problems with data models
Quote: easily split independent sections of a database [»coddEF_1990]
Quote: existing database models are highly structured, rigid, and simplistic
[»kentW_1978]
Topic: database agents (10 items)
Topic: database as a model of reality (25 items)
Topic: database entities (12 items)
Topic: database keys and indexing (18 items)
Topic: database record (22 items)
Topic: database schema (29 items)
Topic: entity-relationship database model (22 items)
Topic: existence of database entities (19 items)
Topic: fact-based analysis for database design (15 items)
Topic: fundamental concepts such as type, attributes, relationships are all the same (37 items)
Topic: heterogeneous database (6 items)
Topic: loosely structured data (20 items)
Topic: network and hierarchical databases (4 items)
Topic: relational database (35 items)
Topic: uniform data model
(19 items)
Group: data type (34 topics, 730 quotes)
Group: program design (13 topics, 454 quotes)
Group: hypertext (44 topics, 786 quotes)
Group: information (46 topics, 1160 quotes)
Group: natural language (16 topics, 539 quotes)
Group: relationship information (5 topics, 69 quotes)Topic: classification (65 items)
Topic: collection class (11 items)
Topic: data as a named set of data objects (22 items)
Topic: database implementation (18 items)
Topic: design for change (76 items)
Topic: models of parallel computation (33 items)
Topic: object-oriented databases (15 items)
Topic: object-oriented design (30 items)
Topic: object-oriented modelling language (6 items)
Topic: problem of classifying information (42 items)
Topic: Thesa data model
(58 items)