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COMPONENTS OF A TABLE

            The important components of a table are:
            1.  Field or Attribute
                 The columns in a table are known as fields         or attributes . A field is a part of record, which
                 consists of a single piece of data. A field stores one type of information about all the objects

                 or items. Every field has a data type that determines the type of values that can be stored
                 under it.

               Note : Data types are used to declare the fields of a table. A data type determines the type of data in
               it. Once the data type is defined, we cannot enter a different type of data in it. If we try to do so, an
               error message will be displayed.

            Field Data Types: The various data types available in Access are described in the table given
            below.


              Data Types                                           Descriptions

             Short Text       It is used to store text or a combination of text and numbers that does not require

                              calculations, such as addresses, phone numbers, etc. The field with this data type can
                              have a maximum of 255 characters.


             Long Text        It is used to store lengthy text, i.e.i up to 65,536 characters. It can be used for storing
                              detailed information such as the synopsis of a book or a patient's medical history.


             Number           It is used for numeric data that can be used in calculations.

             Date/Time        It stores date and time values. You can display the dates and times in various formats.


             Currency         It stores currency values and then displays them in different formats.


             AutoNumber       It stores an integer that increments automatically as you add records.


             Yes/No           This can have only one of two possible values such as Yes/No, True/False or On/Off.

             OLE              This stores graphics or objects such as Microsoft Excel worksheet or Microsoft Word

                              document.

             Hyperlink        The fields with this data type can store links to websites or email addresses.

             Attachment       This data type is used to attach images, spreadsheet files, documents, charts and other

                              types of supported files to the records in your database, much similar to the manner you
                              attach files to the emails.

             Calculated       Fields with this data type store results of a calculation. The calculation must refer to
                              other fields in the same table.



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