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    Output:
                                 +--------+----------+---------------+------------+-----+
                                 | Stu_id | Stu_name | Subject_group | DOB        | Age |
                                 +--------+----------+---------------+------------+-----+
                                 | 104    | Rani     | Science       | 2002-04-01 | 20  |
                                 +--------+----------+---------------+------------+-----+
                  In this case, the outer query's result is totally dependent on the result of the inner subquery.
                  Rules to be followed for subqueries are as follows:

                      A subquery must be enclosed within parentheses ().
                      A subquery is always executed before the main (outer) query.

                      A subquery can return a single value or multiple values.
                      Subqueries can be used with SELECT, FROM, or WHERE clauses.
                      Use appropriate comparison operators such as =, IN, ANY, ALL, or EXISTS with subqueries.

                      The data type of the column used in the subquery must match the data type in the outer query
                      for comparison.
                      Subqueries cannot manipulate their results internally, therefore ORDER BY clause cannot be
                      added inside a subquery. An ORDER BY clause can be used in the main SELECT statement (outer
                      query), where it will appear as the last clause.

                  Subquery with Operators

                  You can use different types of operators with subqueries. Let us understand some of them. For
                  example, consider the following Table - PRODUCT

                                                             Table-PRODUCT
                                                  P_id            P_name           Quantity

                                                  1001        Pen                     100

                                                  1002        Pencil                  200

                                                  1003        Drawing Sheet           130

                                                  1004        Stencil                 145

                                                  1005        Eraser                   90

                       SELECT P_name FROM PRODUCT WHERE Quantity > 100;
                  Only those rows where the product quantity is greater than 100 will be selected. The P_name values
                  of these records will be considered and displayed.

                  Output:
                                                           +---------------+
                                                           | P_name        |
                                                           +---------------+
                                                           | Pencil        |
                                                           +---------------+
                                                           | Drawing Sheet |
                                                           +---------------+
                                                           | Stencil       |
                                                           +---------------+

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