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Relational database

Relational database
In the relational model, each table schema must identify a column or group of columns, called the primary key, to uniquely identify each row. A relationship can then be established between each row in the table and a row in another table by creating a foreign key, a column or group of columns in one table that points to the primary key of another table. The relational model offers various levels of refinement of table organization and reorganization called database normalization. (See Normalization below.) The database management system (DBMS) of a relational database is called an RDBMS, and is the software of a relational database. In relational databases, each data item has a row of attributes, so the database displays a fundamentally tabular organization. Relational databases are both created and queried by DataBase Management Systems (DBMSs). Terminology[edit] Relational database terminology. Relations or Tables[edit] Tuples by definition are unique. Base and derived relations[edit]

http://en.wikipedia.org/wiki/Relational_database

Related:  FuzzyMethods

T-norm fuzzy logics T-norm fuzzy logics are a family of non-classical logics, informally delimited by having a semantics which takes the real unit interval [0, 1] for the system of truth values and functions called t-norms for permissible interpretations of conjunction. They are mainly used in applied fuzzy logic and fuzzy set theory as a theoretical basis for approximate reasoning. T-norm fuzzy logics belong in broader classes of fuzzy logics and many-valued logics. ATC/DDD Anatomical-therapeutic-chemical Classification with Defined Daily Doses ATC-Classification with Defined Daily Doses DIMDI publishes the annually updated official version of the German Anatomical Therapeutic Chemical (ATC)-Classification with defined daily doses (DDD) since January 1st, 2004. You can download a PDF file of the official German ATC-Classification (in German) for free: ATC/DDD as PDF file for free at downloadcenter Classification

Database Database management systems (DBMSs) are specially designed software applications that interact with the user, other applications, and the database itself to capture and analyze data. A general-purpose DBMS is a software system designed to allow the definition, creation, querying, update, and administration of databases. Well-known DBMSs include MySQL, MariaDB, PostgreSQL, SQLite, Microsoft SQL Server, Oracle, SAP HANA, dBASE, FoxPro, IBM DB2, LibreOffice Base and FileMaker Pro. A database is not generally portable across different DBMSs, but different DBMSs can interoperate by using standards such as SQL and ODBC or JDBC to allow a single application to work with more than one database. Terminology and overview[edit]

Defuzzification Defuzzification is the process of producing a quantifiable result in fuzzy logic, given fuzzy sets and corresponding membership degrees. It is typically needed in fuzzy control systems. These will have a number of rules that transform a number of variables into a fuzzy result, that is, the result is described in terms of membership in fuzzy sets. For example, rules designed to decide how much pressure to apply might result in "Decrease Pressure (15%), Maintain Pressure (34%), Increase Pressure (72%)". Defuzzification is interpreting the membership degrees of the fuzzy sets into a specific decision or real value.

DIMDI - ATC/DDD Anatomical-therapeutic-chemical Classification with Defined Daily Doses ATC-Classification with Defined Daily Doses DIMDI publishes the annually updated official version of the German Anatomical Therapeutic Chemical (ATC)-Classification with defined daily doses (DDD) since January 1st, 2004. You can download a PDF file of the official German ATC-Classification (in German) for free: Object-relational database Example of an object-oriented database model.[1] An object-relational database can be said to provide a middle ground between relational databases and object-oriented databases (OODBMS). In object-relational databases, the approach is essentially that of relational databases: the data resides in the database and is manipulated collectively with queries in a query language; at the other extreme are OODBMSes in which the database is essentially a persistent object store for software written in an object-oriented programming language, with a programming API for storing and retrieving objects, and little or no specific support for querying. Overview[edit] The ORDBMS (like ODBMS or OODBMS) is integrated with an object-oriented programming language. The characteristic properties of ORDBMS are 1) complex data, 2) type inheritance, and 3) object behavior.

Fuzzy associative matrix A fuzzy associative matrix expresses fuzzy logic rules in tabular form. These rules usually take two variables as input, mapping cleanly to a two-dimensional matrix, although theoretically a matrix of any number of dimensions is possible. Suppose a professional is tasked with writing fuzzy logic rules for a video game monster. Object database Example of an object-oriented model[1] Object databases have been considered since the early 1980s.[2] Overview[edit] Cognitive map A cognitive map (also: mental map or mental model) is a type of mental representation which serves an individual to acquire, code, store, recall, and decode information about the relative locations and attributes of phenomena in their everyday or metaphorical spatial environment. The concept was introduced by Edward Tolman in 1948.[1] Cognitive maps have been studied in various fields, such as psychology, education, archaeology, planning, geography, cartography, architecture, landscape architecture, urban planning, management and history.[2] As a consequence, these mental models are often referred to, variously, as cognitive maps, mental maps, scripts, schemata, and frames of reference. Cognitive maps serve the construction and accumulation of spatial knowledge, allowing the "mind's eye" to visualize images in order to reduce cognitive load, enhance recall and learning of information. Neurological basis[edit]

National drug databases - EU Explanatory note: ATC = database allows search according to ATC classification. Rx/OTC = database allows search according to Rx/OTC. Germany - Fachinformation or Summary of Product Characteristics and Package Leaflet, Public Assessment Reports (for medicines registered via NP or where BfArM is RMS). For detailed overview see German drug databases list.

Data access object Although this design pattern is equally applicable to most programming languages, most types of software with persistence needs, and most types of databases, it is traditionally associated with Java EE applications and with relational databases accessed via the JDBC API because of its origin in Sun Microsystems' best practice guidelines[1] ("Core J2EE Patterns") for that platform. Advantages[edit] The advantage of using data access objects is the relatively simple and rigorous separation between two important parts of an application that can and should know almost nothing of each other, and which can be expected to evolve frequently and independently. Changing business logic can rely on the same DAO interface, while changes to persistence logic do not affect DAO clients as long as the interface remains correctly implemented. Tools and frameworks[edit] See also[edit]

Lotfi A. Zadeh Lotfali Askar Zadeh (born February 4, 1921), better known as Lotfi A. Zadeh, is a mathematician, electrical engineer, computer scientist, artificial intelligence researcher and professor emeritus[1] of computer science at the University of California, Berkeley. Life and career[edit] Zadeh was born in Baku, Azerbaijan SSR,[2] as Lotfi Aliaskerzadeh,[3] to an Iranian Azerbaijanis father from Ardabil, Rahim Aleskerzade, who was a journalist on assignment from Iran, and a Russian Jewish mother,[4] Fanya Koriman, who was a pediatrician.[5] The Soviet government at this time courted foreign correspondents, and the family lived well while in Baku.[6] Zadeh attended elementary school for three years there,[6] which he has said "had a significant and long-lasting influence on my thinking and my way of looking at things."[7]

ICD-10 Version:2016 Advanced search lets you search selected properties of the classification. You could search all properties or a selected subset only First, you need to provide keywords in the Search Text field then check the properties that you'd like to include in the search. The system will search for the keywords in the properties that you've checked and rank the results similar to a search engine

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