What is join, Polymorphism in java, Exception handling in java, Difference between array list and list linked list, some SQL queries based on count,Max,sum function.

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Join is used to combine rows from two or more tables based on a related column. Polymorphism allows objects of different classes to be treated as objects of a common superclass. Exception handling is used to handle errors and exceptions in Java. ArrayList and LinkedList are both implementations of the List interface in Java, with differences in performance and usage. SQL queries can be used to perform operations like counting, finding maximum values, and calculating sums.

Join in SQL is used to combine rows from two or more tables based on a related column, such as INNER JOIN, LEFT JOIN, RIGHT JOIN, etc.
Polymorphism in Java allows objects of different classes to be treated as objects of a common superclass, enabling flexibility and reusability in code.
Exception handling in Java involves try, catch, and finally blocks to handle errors and exceptions gracefully, preventing program crashes.
ArrayList and LinkedList are both implementations of the List interface in Java, with ArrayList being faster for accessing elements by index and LinkedList being faster for adding or removing elements in the middle of the list.
SQL queries for count, max, and sum functions can be written using aggregate functions like COUNT(), MAX(), and SUM() to perform calculations on data in a database.

What is join, Polymorphism in java, Exception handling in java, Difference between array list and list linked list, some SQL queries based on count,Max,sum function.

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