Danaher Customer Service Associate Interview Questions and Answers

There are four types of joins in SQL: INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

• INNER JOIN: Returns rows when there is at least one match in both tables.

• LEFT JOIN: Returns all rows from the left table and the matched rows from the right table.

• RIGHT JOIN: Returns all rows from the right table and the matched rows from the left table.

• FULL JOIN: Returns rows when there is a match in one of the tables.

List is an ordered collection of elements with duplicates allowed, while set is an unordered collection of unique elements.

• List maintains the order of elements, while set does not guarantee any specific order.

• List allows duplicate elements, while set does not allow duplicates.

• List is implemented using classes like ArrayList, LinkedList, etc., while set is implemented using classes like HashSet, TreeSet, etc.

Map is a collection of key-value pairs where each key is unique, while a set is a collection of unique elements with no duplicate values.

• Map allows duplicate values but keys must be unique, while set does not allow duplicates.

• Map is accessed using keys, while set is accessed using elements.

• Example: Map - {1: 'apple', 2: 'banana'}, Set - {'apple', 'banana'}

Fibonacci program generates the Fibonacci sequence up to a specified number of terms.

• Start with two variables initialized to 0 and 1

• Use a loop to calculate the next Fibonacci number by adding the previous two numbers

• Repeat the process until the desired number of terms is reached