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Data Modification

Critical function of DBMS: changing data
  • insert new tuples into tables
  • delete existing tuples from tables
  • update values within existing tuples
E.g. 

insert into Enrolments(student,course,mark)
values (3312345, 5542, 75);

update Enrolments set mark = 77
where  student = 3354321 and course = 5542;

delete Enrolments where student = 331122333;