Query languageComputer language used to make queries into databases and information systems A query language, also known as data query language or database query language (DQL), is a computer language used to make queries in databases and information systems. In database systems, query languages rely on strict theory to retrieve information. A well known example is the Structured Query Language (SQL).
Database designDatabase design is the organization of data according to a database model. The designer determines what data must be stored and how the data elements interrelate. With this information, they can begin to fit the data to the database model. A database management system manages the data accordingly. Database design is a process that consists of several steps. Conceptual data modelingThe first step of database design involves classifying data and identifying interrelationships.Row (database)Record in a relational database table In a relational database, a row or "record" or "tuple", represents a single, implicitly structured data item in a table. A database table can be thought of as consisting of rows and columns. Each row in a table represents a set of related data, and every row in the table has the same structure. For example, in a table that represents companies, each row might represent a single company.Result setA result set is the set of results returned by a query, usually in the same format as the database the query is called on. For example, in SQL, which is used in conjunction with relational databases, it is the result of a SELECT query on a table or view and is itself a non-permanent table of rows, and could include metadata about the query such as the column names, and the types and sizes of each column.Relational databaseA relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970. A Relational Database Management System (RDBMS) is a type of database management system that stores data in a structured format using rows and columns. Many relational database systems are equipped with the option of using SQL (Structured Query Language) for querying and updating the database.
Data dictionaryA data dictionary, or metadata repository, as defined in the IBM Dictionary of Computing, is a "centralized repository of information about data such as meaning, relationships to other data, origin, usage, and format". Oracle defines it as a collection of tables with metadata.
DatabaseAn SQL select statement and its resultIn computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and analyze the data. The DBMS additionally encompasses the core facilities provided to administer the database.Database normalizationDatabase normalization is the process of structuring a relational database in accordance with a series of normal forms to reduce data redundancy and improve data integrity. It was first proposed by British computer scientist Edgar F. Codd as part of his relational model. Normalization entails organizing the columns (attributes) and tables (relations) of a database to ensure that their dependencies are properly enforced by database integrity constraints.
Second normal formSecond normal form (2NF) is a level of database normalization defined by English computer scientist Edgar F. Codd. A relation (or a table, in SQL) is in 2NF if it is in first normal form (1NF) and contains no partial dependencies. A partial dependency occurs when a non-prime attribute (that is, one not part of any candidate key) is functionally dependent on only a proper subset of the attributes making up a candidate key.
Function (computer programming)In computer programming, a function (also procedure, method, subroutine, routine, or subprogram) is a callable unit of software logic that has a well-formed interface and behavior and can be invoked multiple times. Callable units provide a powerful programming tool. The primary purpose is to enable the decomposition of a large and/or complicated problem into chunks that have relatively low cognitive load.
Abstraction (computer science)In software, an abstraction provides access while hiding details that otherwise might make access more challenging. It focuses attention on details of greater importance. Examples include the abstract data type which separates use from the representation of data and functions that form a call tree that is more general at the base and more specific towards the leaves.
Order byAn ORDER BY clause in SQL specifies that a SQL SELECT statement returns a result set with the rows being sorted by the values of one or more columns. The sort criteria do not have to be included in the result set (restrictions apply for SELECT DISTINCT, GROUP BY, UNION [DISTINCT], EXCEPT [DISTINCT] and INTERSECT [DISTINCT].) The sort criteria can be expressions, including column names, user-defined functions, arithmetic operations, or CASE expressions.*As an Amazon Associate I earn from qualifying purchases.