Page 157 - Informatics_Practices_Fliipbook_Class12
P. 157

Pin_                       Dept_
               ID    FName    LName    Gender      Address        City                DOB      Salary         Phone
                                                                           Code                         No
             E0001    Raj      Reddy      M     West Godavari   Andhra    534197   1980-06-13  100000    2    NULL
                                                                Pradesh
             E0002   Dhiraj    Bora       M     Dispur,        Guwahati   781005   1975-09-30  85000     1    NULL
                                                Kamrup, Assam
             E0003  Muskan    Taneja      F     8/33, Geeta      Delhi    110031   1990-01-25  100000    2    NULL
                                                Colony
             E0004   Hiten    Oberoi      M     15, Dimna     Jamshedpur  831018   1985-06-24  100000    4    NULL
                                                Road, Mango
             E0005   Anshul   Verma       M     House 10,        Noida    201304   1990-01-01  100000    1    NULL
                                                Sector 16,
                                                Gautam Budh
                                                Nagar
             E0006    Rajit    Gadh       F     12, Beldih    Jamshedpur  831001   1960-05-07  60000     4    NULL
                                                Triangle,
                                                Bistupur
             E0007   Taran    Adarsh      M     B-76, CST       Mumbai    400098   1965-01-13  70000     5    NULL
                                                Road, Kalina,
                                                Santacruz East
             E0008   Naval    Dhingra     M     E-14 Vivek       Delhi    110095   1975-08-04  70000     2    NULL
                                                Vihar
             E0009  Naveen     Basra      F     28, Aambagan   Jamshedpur  831001  1980-09-24  60000     4    NULL
                                                Road, Sakechi
             E0010   Savita   Ambedkar    F     C-49, G-Block,   Mumbai   400051   1987-07-11  50000     5    NULL
                                                Bandra Kurla,
                                                Bandra East

                                          Table 11.6a: Phone attribute is assigned value NULL
            To enforce NOT NULL constraint on the attribute Phone, we will use the following statement instead of the above
            ALTER statement:
            ALTER TABLE EMPLOYEE ADD Phone DECIMAL(10,0) NOT NULL;
            On executing the above statement, Phone attribute of the tuples that already exist in the EMPLOYEE table will be
            assigned value 0 as we have not specified a default value of the Phone attribute (see Table 11.6b)


                                                                             Pin_                       Dept_
              ID    FName    LName    Gender       Address         City                DOB      Salary         Phone
                                                                            Code                         No
            E0001    Raj      Reddy      M     West Godavari     Andhra     534197  1980-06-13  100000    2      0
                                                                 Pradesh
            E0002   Dhiraj    Bora       M     Dispur, Kamrup,   Guwahati   781005  1975-09-30   85000    1      0
                                               Assam
            E0003  Muskan    Taneja      F     8/33, Geeta        Delhi     110031  1990-01-25  100000    2      0
                                               Colony
            E0004   Hiten    Oberoi      M     15, Dimna Road,   Jamshedpur  831018  1985-06-24  100000   4      0
                                               Mango
            E0005   Anshul   Verma       M     House 10, Sector   Noida     201304  1990-01-01  100000    1      0
                                               16, Gautum Budh
                                               Nagar
            E0006    Rajit    Gadh       F     12, Beldih      Jamshedpur   831001  1960-05-07   60000    4      0
                                               Triangle, Bistupur


                                                                                        Database Query using SQL  143
   152   153   154   155   156   157   158   159   160   161   162