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On executing the above statement, we get the result as given in Table 11.6b:

                        Field       Type          Null         Key         Default         Extra
                         ID        char(5)         NO          PRI          NULL

                       FName      varchar(20)      NO                       NULL
                       LName      varchar(20)      NO                       NULL
                      Gender       char(1)         NO                       NULL
                      Address     varchar(30)     YES                       NULL
                        City      varchar(20)     YES                       NULL
                      Pin_Code     char(6)        YES                       NULL
                        DOB          date         YES                       NULL

                       Salary       int(11)        NO                       NULL
                      Dept_No       int(11)       YES                       NULL
                       Phone     decimal(10,0)    YES                    9999999999
                      MOBILE     decimal(10,0)    YES                    9999999999
                       EMAIL      varchar(50)     YES                       NULL

                          Table 11.6b: Structure of EMPLOYEE table after modifying Dept_No
        Drop Attributes

        To drop an attribute from a table, we use the ALTER TABLE statement with the DROP keyword. The syntax of the
        ALTER TABLE DROP statement is as follows:

               ALTER TABLE table_name DROP attribute;
        For example, to drop the attributes Phone, Mobile, and EMAIL from the EMPLOYEE table, we can execute
        the following SQL statements:

               ALTER TABLE EMPLOYEE DROP Phone;
               ALTER TABLE EMPLOYEE DROP Mobile;
               ALTER TABLE EMPLOYEE DROP EMAIL;
        As before,  we describe the modified table EMPLOYEE as follows:
               DESC EMPLOYEE;
        On executing the above statement, we get the result as given in Table 11.6c:

                        Field       Type          Null         Key         Default         Extra
                         ID        char(5)         NO          PRI          NULL

                       FName      varchar(20)      NO                       NULL
                       LName      varchar(20)      NO                       NULL
                      Gender       char(1)         NO                       NULL
                      Address     varchar(30)     YES                       NULL
                        City      varchar(20)     YES                       NULL
                      Pin_Code     char(6)        YES                       NULL
                        DOB          date         YES                       NULL

                       Salary       int(11)        NO                       NULL
                      Dept_No       int(11)       YES                       NULL

                     Table 11.6c: Structure of EMPLOYEE table after dropping the Phone attribute
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