Natural key - A natural key identifies a database record using attributes that already have meaning in the business domain.
Navigational database - A navigational database is a database accessed by following defined paths between related records.
Nested Loop - A nested loop is a process in which an inner operation runs for each item handled by an outer operation.
Nested Relation - A nested relation is a relation whose tuples can contain relation-valued attributes: a value can itself be a collection of structured records.
Network Data Model - The network data model organizes database records through explicitly defined relationships that can form a network rather than a single tree.
Network on a chip - A network on a chip, usually written network-on-chip or NoC, is a communication network inside an integrated circuit.
Network transparency - Network transparency is the property of a system that hides some details of network communication from its users or applications.
No-information - No-information, in the referenced database literature, describes a missing-value situation in which neither the value nor whether an applicable value exists...
Non-existent value - A non-existent value, in the referenced database literature, is a missing-value situation where the relevant value does not exist, rather than merely being...
Non-personal data - Non-personal data is information that does not relate to an identified or identifiable individual under the applicable definition of personal data.
Non-relational database - A non-relational database primarily organizes and accesses data through models other than the traditional relational table model.
Non-uniform memory access - Non-uniform memory access, or NUMA, is a computer architecture in which the time required to access main memory depends partly on where that memory is...
Nonprime attribute - A nonprime attribute is an attribute that belongs to none of a relation schema's candidate keys.
Nontrivial MVD - A nontrivial multivalued dependency, or nontrivial MVD, is a dependency X multidetermines Y on relation schema R for which Y is not a subset of X and X...
Normal form - A normal form is a specified set of conditions used to assess the structure of a relational database schema with respect to dependencies and redundancy.
Normalization Algorithm - A normalization algorithm is a systematic procedure for constructing or decomposing relational schemas to satisfy a specified normal form under stated...
Novelty detection - Novelty detection identifies new observations that differ substantially from a reference pattern learned from data treated as normal.
Null Value - A null value in SQL is a marker representing missing or unknown information rather than an ordinary value such as zero or a text string.
OAuth - OAuth is an authorization framework through which a client can obtain limited access to a protected service.
Object Data Model - An object data model represents information through objects with identity, state and, in object-oriented approaches, associated behavior.
Object - role modeling - Object - role modeling, often abbreviated ORM, is a conceptual data-modeling approach that describes a business domain through facts and the roles that...
Object storage - Object storage is a way to store data as individually addressable objects, each containing data and associated metadata.
Observability (software) - Observability in software is the ability to understand a system's internal behavior by examining the information it exposes.
OLAP cube - An OLAP cube is a multidimensional analytical model that organizes measures, such as sales or quantity, by dimensions such as product, location and time.
One-to-many (data model) - A one-to-many relationship connects one instance of an entity type to potentially several instances of another, while each instance on the many side relates...
One-to-one (data model) - A one-to-one relationship is a data-model relationship in which each instance on either side is associated with at most one instance on the other side.
Online complex processing - Online complex processing, or OLCP, is a historical database-workload term for demanding online operations that can combine complex queries, multi-statement...
Ontology alignment - Ontology alignment identifies and represents meaningful correspondences between entities in different ontologies.
Ontology-based data integration - Ontology-based data integration uses an ontology as an explicit model of meaning to connect information from different sources.
Ontology merging - Ontology merging is the construction of a combined ontology from two or more source ontologies.
Open access - Open access is the online availability of scholarly work without a reader payment barrier, with reuse permissions an important part of fuller definitions.
Operational data store - An operational data store, or ODS, is a data store that integrates operational information to support a relatively current, detailed view of business activity.
Operational database - An operational database stores and manages information used to carry out an organization's ongoing activities.
Operational historian - An operational historian is a system for collecting, storing and retrieving time-stamped information from operational processes, especially industrial...
Operational system - An operational system is an information system that supports an organization's ongoing business activities.
Optical Multi-Tree with Shuffle Exchange - Optical Multi-Tree with Shuffle Exchange, usually abbreviated OMTSE, is a research interconnection architecture for parallel computers.
Ordered key - value store - An ordered key - value store is a data store that associates keys with values while maintaining a defined ordering of the keys.
Ordinal tree - An ordinal tree is a rooted tree in which each node's children have a defined order.
Outer Join - An outer join combines matching rows from its inputs while also preserving specified unmatched rows.
PACELC design principle - PACELC is a design principle for reasoning about replicated distributed databases.
Parallel algorithm - A parallel algorithm is a method for solving a problem that allows multiple operations to proceed at the same time.
Parallel breadth-first search - Parallel breadth-first search is a graph-search method that uses simultaneous work to explore vertices in increasing distance from a starting vertex.
Parallel computation thesis - The parallel computation thesis is a principle in computational complexity that relates parallel running time to sequential memory use, up to polynomial...
Parallel computing - Parallel computing is the use of multiple computing resources at the same time to perform a computational task.
Parallel mesh generation - Parallel mesh generation creates a computational mesh using multiple processing resources at the same time.
Parallel programming model - A parallel programming model is the set of concepts and rules programmers use to express work that can execute simultaneously.