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Below we describe some important data types:
        1.  Numeric: The following data types may be used to specify that an attribute can contain numeric data:
            a.  INT  or  INTEGER:  The  datatype  INT  is  used  for  specifying  32-bit  integers.  For  example,  the  attribute
               Salary of an employee may be of type INTEGER.
               Examples of type INT
               Valid

               0
               -0
               1234
               1234567890
               -1234567890
               123.45 (digits to the right of the decimal point are truncated)
               Invalid
               1,23,456 (punctuation characters not allowed)
               29-01-22 (punctuation characters not allowed)
               -2147483649 (beyond valid range)
               2147483648 (beyond valid range)
               98765432100.1234 (beyond valid range)


               INT or INTEGER: 32-bit integer.


            b.  SMALLINT: The data type SMALLINT is used to store small integers (typically 16-bit integers). For example,
               the attribute Dept_No of the department may be of type SMALLINT.
               Examples of type SMALLINT
               Valid
               0
               -0
               1234
               -32768

               32767
               123.45 (digits to the right of the decimal point are truncated)
               Invalid
               1,23,456 (punctuation characters not allowed)
               29-01-22 (punctuation characters not allowed)
               -32769 (beyond valid range)
               32768 (beyond valid range)
               987654321.1234 (beyond valid range)



               SMALLINT: Typically 16-bit integer.


            c.  DECIMAL(L, D): It is used to denote a fixed point decimal. The arguments  L and D denote the maximum
               number of digits and number of digits to the right of the decimal point, respectively. For example, attribute
               type DECIMAL(6,2) indicates that the attribute values may lie in the interval [-9999.99, 9999.99].
               When  the  value  of  an  attribute  of  DECIMAL  type  lies  outside  its  limits,  the  effect  is  system  defined.

          242  Touchpad Informatics Practices-XI
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