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    RETRIEVING RECORDS FROM TABLE

                     The SELECT command retrieves zero or more rows from a table. It helps us to join information from
                     different tables and filter specific information as per the required criteria. The SELECT command is the
                     most useful DML command. The ‘SELECT’ statement has many optional clauses which are as follows:

                        WHERE specifies the criteria according to which rows are retrieved.
                        ORDER BY specifies an order (Ascending or Descending) to return the rows.

                     The syntax to execute the SELECT queries:

                          SELECT * FROM table_name;
                     To display all the data in the table:

                          SELECT * FROM Student;

                     The preceding command will display the following output:
                                            +-----------+-----------+----------+-------+
                                            | StudentID | FirstName | LastName | Marks |
                                            +-----------+-----------+----------+-------+
                                            |     10001 | Amit      | Sharma   |   450 |
                                            |     10002 | Divya     | Kaushik  |   450 |
                                            |     10003 | Aadarsh   | Kumar    |   450 |
                                            +-----------+-----------+----------+-------+

                     To get details of the list of students whose LASTNAME is Kumar:
                          SELECT * FROM Student WHERE LastName = "Kumar";

                     The preceding command will display the following output:

                                            +-----------+-----------+----------+-------+
                                            | StudentID | FirstName | LastName | Marks |
                                            +-----------+-----------+----------+-------+
                                            |     10003 | Aadarsh   | Kumar    |   450 |
                                            +-----------+-----------+----------+-------+

                     To get details of the list of students in ascending order of FirstName:

                          SELECT * FROM Student ORDER BY FirstName ASC;

                     The preceding command will display the following output:
                                           +-----------+-----------+----------+-------+
                                           | StudentID | FirstName | LastName | Marks |
                                           +-----------+-----------+----------+-------+
                                           |     10003 | Aadarsh   | Kumar    |   450 |
                                           |     10001 | Amit      | Sharma   |   450 |
                                           |     10002 | Divya     | Kaushik  |   450 |
                                           +-----------+-----------+----------+-------+

                     We can also use the wildcard characters ( _ and %) with the SELECT command alongwith LIKE operator
                     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%';

                                                                                        #Info Hub (Introduction to MySQL) 161

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