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We can also use the wildcards (_and %) with the SELECT command to specify conditions. The _ wildcard
                 denotes a single character, on the other hand the % wildcard denotes the multiple characters:

                      SELECT FirstName, Marks FROM Student WHERE LastName like 'K%';

                                                       +-----------+-------+
                                                       | FirstName | Marks |
                                                       +-----------+-------+
                                                       | Divya     |   450 |
                                                       | Aadarsh   |   450 |
                                                       +-----------+-------+

                      SELECT Marks FROM Student WHERE FirstName like 'D%';

                                                              +-------+
                                                              | Marks |
                                                              +-------+
                                                              |   450 |
                                                              +-------+

                 UPDATING RECORDS IN A TABLE


                 Sometime, you may need to change the detail 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    |   450 |
                                        +-----------+-----------+----------+-------+


                 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;





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