Description+of+a+field,+file,+record+and+key+field+database

 =__Four different databases include:__ = __**A Field** __ A database field is a space chosen for a particular item of information. A tax form, for example, contains a number of fields: In database systems, fields are the smallest units of information you can access. In spreadsheets, fields are called cells __**A File** __  A database file is a mass of random information, or resource for storing information, which is available to a computer program and is usually based on some kind of long-lasting storage. A file is //long-lasting// in the sense that it remains available for programs to use after the current program has finished. __**A Record** __ In database management systems a record is a complete set of information. Records are composed of fields, each of which contains one item of information. A set of records makes up a file. For example, a personnel file might contain records that have three fields: a name field, an address field, and a phone number field. __**A Key Field** __ What is a Key field in a Database and How should I choose one ? Keys are crucial to a table structure for many reasons, some of which are identified below :
 * A file
 * A field
 * A record
 * A key field
 * one for your name,
 * <span style="font-family: 'Palatino Linotype','Book Antiqua',Palatino,serif; font-size: 18px;">one for your Social Security number,
 * <span style="font-family: 'Palatino Linotype','Book Antiqua',Palatino,serif; font-size: 18px;">one for your income, and so on.

§ <span style="font-family: 'Palatino Linotype','serif'; font-size: 18px;">They ensure that each record in a table is precisely identified. § <span style="font-family: 'Palatino Linotype','serif'; font-size: 18pt;"> They help establish and enforce various types of integrity. § <span style="font-family: 'Palatino Linotype','serif'; font-size: 18pt;"> They serve to establish table relationships.