Lowe's Software Engineer Interview Questions, Process, and Tips

Hash map is a data structure that stores key-value pairs and uses a hash function to map keys to indices in an array.

• Hash function is used to convert the key into an index in the array

• Collisions occur when two keys map to the same index, which can be resolved using separate chaining or open addressing

• Load factor is the ratio of number of elements to the size of the array, and affects the performance of hash map

• Operatio...read more

SQL query to get 2nd highest salary

• Use ORDER BY and LIMIT to get the highest salary

• Use subquery to exclude the highest salary and get the 2nd highest

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 1,1