Logical Data Modeling - Unique Key

Data System Architecture

About

A Unique Key identifies:

A primary key is also a unique key

The set of all unique keys defines the atomic level of the data.

Implementation

See Index - Unique Index




Discover More
Data Modeling Chebotko Logical
Cassandra - Primary Key

This page talks the primary key of a cassandra table. The primary key is composed of: in first position: the partition keys columns that defines the data location and partition in successive position:...
Star Schema
Dimensional Data Modeling - Dimension (Perspective)

A dimension is a part of a dimensional schema and provide the basis for analyzing data through slicing and dicing A dimension is just a set of descriptif attribute that are generally grouped: in a...
Star Schema
Dimensional Data Modeling - Fact Table

A fact table is a table that stores fact where a fact can be seen as the representation of an event. It's also known as: Transactional history Unalterable fact. (The content of this kind of table...
Star Schema
Dimensional Data Modeling - Grain

The grain is the combination of all lower hierarchy level of the descriptif attribute of a relation (table or query). If you query only a table, the unique key of this table is the grain If you query...
HTML - Element's unique identifier (Id Attribute)

The DOM specification gives the concept of an element's unique identifier (ID) An element's unique identifier can be used for a variety of purposes, most notably as a way to: link to specific parts...
Data System Architecture
How is used the name attribute in logical data modeling?

A name is a label attribute of an primary element. It's an identifier that specifies a unique key in a specific scope called a namespace. the name of file is unique in a directory. the name of...
Data System Architecture
Index - Unique Index

A unique index is an index data structure that: does not allow duplicate allows Null value implements a unique key. If the key is already present, it will reject the insertion by throwing an error....
Data System Architecture
Logical Data Modeling - (Atomic|Indivisible)

Atomic means indivisible. Atomic data is the most detailed information collected. Such data cannot be subdivided further and is said to be an the lowest grain. In data analysis, this is in general data...
Data System Architecture
Logical Data Modeling - Business Key

A business key is a key that use the business users to identify uniquely an entity. It's then also a unique key. The business key is a meaningful/business code based generally on the concatenation of...
Data System Architecture
Logical Data Modeling - Entity Integrity (Uniqueness|No Duplicate|Distinct)

Entity integrity concerns the concept of uniqueness (also called no duplicate) Uniqueness is enforced with: primary key unique key (on a column or indice) Entity integrity is an integrity rule...



Share this page:
Follow us:
Task Runner