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SELECT Marks FROM Student WHERE FirstName like ‘D%’;                            +-------+
                                                                                                      | Marks |
                                                                                                      +-------+
                                                                                                      |   480 |
                                                                                                      +-------+
                  Updating Records in a Table

                  Sometime, you may need to change the details inserted into a table. In that case, the UPDATE
                  command will work. The syntax of the UPDATE command is:

                      UPDATE table_name SET field_change=value WHERE field_criteria=value;

                  Let us change the marks of the student having 10002 as StudentID from 480 to 485 by using the
                  following command:

                      UPDATE Student SET Marks = 485 where StudentID = 10002;
                                       +-----------+-----------+----------+-------+
                                       | StudentID | FirstName | LastName | Marks |
                                       +-----------+-----------+----------+-------+
                                       |     10001 | Amit      | Sharma   |   450 |
                                       |     10002 |  Divya    | Kaushik  |   485 |
                                       |     10003 |  Aadarsh  | Kumar    |   475 |
                                       +-----------+-----------+----------+-------+

                  Removing Records from a Table

                  The DELETE command is used to remove records from a table. The DELETE command can be used in
                  two ways:

                      Without WHERE clause       With the WHERE clause

                  We can remove a specific record by using the WHERE clause with the DELETE command. If we use
                  the DELETE command without the WHERE clause, it will remove all the records from a table. Let us
                  use the DELETE command to remove the record of a student whose LastName is Kumar:

                      DELETE FROM Student WHERE LastName=”Kumar”;
                  To remove all the records, following command is used:

                      DELETE FROM Student;
                  DROP command is used to delete the structure of a table or even the database.

                  Example:

                  To delete the table Student from database:
                      DROP TABLE student;

                      To delete the database School:
                      DROP DATABASE school;












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