Concepts inRepair checking in inconsistent databases: algorithms and complexity

Database

A database is an organized collection of data, today typically in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports processes requiring this information (for example, finding a hotel with vacancies). The term database is correctly applied to the data and their supporting data structures, and not to the database management system (DBMS).
more from Wikipedia

Referential integrity

Referential integrity is a property of data which, when satisfied, requires every value of one attribute (column) of a relation (table) to exist as a value of another attribute in a different (or the same) relation (table). For referential integrity to hold in a relational database, any field in a table that is declared a foreign key can contain only values from a parent table's primary key or a candidate key.
more from Wikipedia

Database design

Database design is the process of producing a detailed data model of a database. This logical data model contains all the needed logical and physical design choices and physical storage parameters needed to generate a design in a Data Definition Language, which can then be used to create a database. A fully attributed data model contains detailed attributes for each entity. The term database design can be used to describe many different parts of the design of an overall database system.
more from Wikipedia

Data integrity

Data Integrity in its broadest meaning refers to the trustworthiness of information over its entire life cycle. In more analytic terms, it is "the representational faithfulness of information to the true state of the object that the information represents, where representational faithfulness is composed of four essential qualities or core attributes: completeness, currency/timeliness, accuracy/correctness and validity/authorization.
more from Wikipedia

Co-NP

In computational complexity theory, co-NP is a complexity class. A problem is a member of co-NP if and only if its complement is in the complexity class NP. In simple terms, co-NP is the class of problems for which efficiently verifiable proofs of no instances, sometimes called counterexamples, exist.
more from Wikipedia

Functional dependency

A functional dependency (FD) is a constraint between two sets of attributes in a relation from a database. Given a relation R, a set of attributes X in R is said to functionally determine another attribute Y, also in R, (written X ¿ Y) if, and only if, each X value is associated with precisely one Y value. Customarily we call X the determinant set and Y the dependent attribute.
more from Wikipedia

Directed acyclic graph

In mathematics and computer science, a directed acyclic graph, is a directed graph with no directed cycles. That is, it is formed by a collection of vertices and directed edges, each edge connecting one vertex to another, such that there is no way to start at some vertex v and follow a sequence of edges that eventually loops back to v again. DAGs may be used to model several different kinds of structure in mathematics and computer science.
more from Wikipedia