A Database framework organizes raw data into a hierarchy of relationships. At the lowest level of this hierarchy, the data is broken down into fundamental building blocks, called fields. A field defines an aspect of that data that is common to all instances of it; for example, a Last Name field would contain persons' last names and a firs name field would contain their first names.
Fields are combined into record. A very simple record might consist of first and last name fields and each record would then contain the full name of a person.
A set of such records is called a table (or in some systems, a data file or file). A phone book is real world example of a table. For each listing in the phone book, there are three fields: one for names, another for addresses and another for phone number-forms a records. The records are alphabetized into a list and bound together to make up the table/phone book.
By breaking up data in to fields and records, a DBMS can access and sort the data very quickly. For example, a DBMS can sort a mailing list alphabetically using the Last Name and First Name fields and sort it ZIP code other by using a ZIP code field.
Fields are combined into record. A very simple record might consist of first and last name fields and each record would then contain the full name of a person.
A set of such records is called a table (or in some systems, a data file or file). A phone book is real world example of a table. For each listing in the phone book, there are three fields: one for names, another for addresses and another for phone number-forms a records. The records are alphabetized into a list and bound together to make up the table/phone book.
By breaking up data in to fields and records, a DBMS can access and sort the data very quickly. For example, a DBMS can sort a mailing list alphabetically using the Last Name and First Name fields and sort it ZIP code other by using a ZIP code field.
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