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databases
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- 1Data BasesDatabases are very powerful tools used in all areas of computing. It is a key computing skill to be able to organised data, create databases and control data using query languages.
- 2Database SoftwareDatabases can also be created and organised using programming languages. Languages like SQL, Visual Basic and Delphi are used to edit databases. Using programming languages means that you can customize a database to do exactly as you want.
- 3Data MiningData mining is a term used to describe analysing large amounts of data to predict future events and trends. As there is so much data now available, people who are able to analyse and understand data are going to be well placed to shape the development of technology
- 4Big DataBig data describes extremely large sets of data. It includes data gathered from many different sources that is then analysed. Big data is often used for making predictions based on patterns that can be seen in the data.
- 5Data SecurityWe put a lot of trust in companies when we give them our personal details. They have a legal obligation to ensure that our data is kept in a secure centralized database. Data encryption is a necessity for any database containing personal data.
- 6EntitiesWhen you build a database you are organizing data about entities. An entity is any item that has its attributes stored as data. An entity could be anything, eg a book, a person, a film, a country or a football team.
- 7AttributesThe details about entities are called attributes. A person is an entity with attributes including age, height and nationality, among many others. When you design a database you need to think about which attributes you want to store. For example, the attributes of a film could include title, duration, certificate, rating, genre, cast, director and year of creation.
- 8TableThe table contains all of the fields and the records for one type of entity. A database may contain more than one table
- 9RecordsRecords contain a collection of data for each entity, usually recorded as a row in the table.
- 10FieldsThe column headings are called the fields. Each field contains a different attribute. For every entity, a unit of data will be entered into each field. Each column might require different data types. For example, the 'Title' column will require data entered as text and the 'Certificate' column will need data entered as numbers.
- 11Unit of dataEach individual piece of data entered is a unit of data. These units are also called data elements.
The primary key contains a unique identifier for each record. To make each record in a database unique we normally assign them a primary key. Even if a record is deleted from a database, the primary key will not be used again. The primary key can be automatically generated and will normally just be a unique number or mix of numbers and letters. - 12What Is SQL
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- Karteikarten am databases , erstellt von kirsty loves SDMN am 28/03/2017.
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