Databases

Data types, fields, queries, records, tables, validation, primary keys and the database concept.

DBMS

Candidates should be able to: describe how a DBMS allows the separation of data from applications and why this is desirable describe the principal features of a DBMS and how they can be used to create customised data handling applications. What is a DBMS? A Database Management System (DBMS) is used to manage a database. …

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Database Table

A relational database is made up of different components, of which the table is most important.  The database table is where all the data in a database is kept. Without tables, there would not be much need for relational databases. In a relational database, a table puts in order the information about a single subject into rows …

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Primary Key (Primary Keyword)

A primary key, also known as the primary keyword, is a key in a relational database that is specific for each record.  It is a unique attribute like a driver’s license number, telephone number with area code or vehicle identification number (VIN).  A relational database must have only one primary key.  Primary keys are usually …

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What is a Database?

A database is any group of information organised for quick search and retrieval through a computer.  Databases are intended to provide the means for the modification, deletion, storage and retrieval of data in connection with different operations.  A database management system (DBMS) utilises queries to pull out information from the database. A database can be saved either as a single file or …

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Database Validation

It is imperative that data is entered correctly in a database.  An automated database has the benefit of having automatic checks to prevent incorrect data from being recorded into the database.  This is a process not available in a manual database. Database validation is a process where the data entered in the database is checked …

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Database Queries

A database query is a way of requesting information from the database.  A database query can be either a select query or an action query.  A select query is a query for retrieving data, while an action query requests for additional actions on the data, like deletion, insertion and updating. For example, a manager can perform a query …

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Database Fields

A database field is a set of data values, of the same data type, in a table.  It is also referred to as a column or an attribute. Most databases also allow fields to hold complex data like pictures, whole files, or even movie clips.  A field that allows same data type does not mean …

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Database Data Types

A database data type refers to the format of data storage that can hold a distinct type or range of values.  When computer programs store data in variables, each variable must be designated a distinct data type.  Some common data types are as follows: integers, characters, strings, floating point numbers and arrays.  More specific data …

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Database Record

A database record is collection of fields about the same person, item, or object in a database. The database record can be thought of as a row of information within a database table. The Database A database is a set of data arranged in a way that a computer program can immediately choose required portions …

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What is a Relational Database?

Candidates should be able to: understand the relationship between entities and tables understand the components of a relational database, such as tables, forms, queries, reports and modules understand the use of logical operators in framing database queries explain the use of key fields to connect tables and avoid data redundancy describe methods of validating data …

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The DBMS

Candidates should be able to: describe how a DBMS allows the separation of data from applications and why this is desirable describe the principal features of a DBMS and how they can be used to create customised data handling applications. What is a DBMS? A Database Management System (DBMS) is used to manage a database. …

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The Database Concept

Candidates should be able to: describe a database as a persistent organised store of data explain the use of data handling software to create, maintain and interrogate a database. What is a database? A database is a persistent, organised store of related data. A database is persistent because the data and structures are stored in …

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