Page 258 - Information_Practice_Fliipbook_Class11
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Value                        CHAR(10)                     No of bytes required

              'IIIT Delhi'                  'IIIT Delhi'                 10
              'IIT Delhi'                   'IIT Delhi '                 10
              'IIT'                         'IIT       '                 10
              '110016'                      '110016    '                 10
               '29-01-2022'                 '29-01-2022'                 10
              'IIT Kharagpur'               'IIT Kharag'                 10
               Invalid
              110016                        not a string
              29-01-2022                    not a string



               CHAR(L): Fixed-length character strings of length L.

        b.   VARCHAR(L): It is used for specifying variable-length character strings where L specifies the maximum length.
            Unlike CHAR, VARCHAR must include a positive integer specifying the maximum allowable length of the string
            as it does not use a default value. For example, declaring Emp_Name to be of type VARCHAR(25) will use one
            byte more than the length of the string being stored. Thus,  the string 'IIT' will require four bytes of memory.
            A string longer than the defined maximum length will result in the truncation of the extra trailing characters. If any
            truncated characters are not blank, SQL will raise an error.
            Examples of type VARCHAR(10)

            Value                    VARCHAR(10) string           No of bytes required
            'IIIT Delhi'             'IIIT Delhi'                 11
            'IIT Delhi'              'IIT Delhi'                  10
            'IIT'                    'IIT'                        4
            '110016'                 '110016'                     7

            '29-01-2022'             '29-01-2022'                 11
            'IIT Kharagpur'          'IIT Kharag'                 11
            Invalid
            110016                   not a string

            29-01-2022               not a string


               VARCHAR(L): Variable-length character strings of length upto L.


        3.  DATE: The data type DATE denotes a date. The standard date format is YYYY-MM-DD. However, SQL also permits
            other formats like  DD_MM_YYYY for storing and retrieving dates.


               DATE: The standard date format is YYYY-MM-DD.




               Time: The data type TIME denotes time. It supports various time formats such as
               HH:MM: SS, HH-MM-SS, HH.MM AM/PM.




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