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This problem deals with finding a target value in a sorted array of integers. The function should return the index of the target value if it is found in the array, or -1 if it is not found.
About this solution: This solution is optimal because it is O(n) time complexity. However, it only works if the array is sorted. If the array is not sorted, this solution will not work.
This technical problem involves writing a SQL query that returns the total revenue for each customer. The table schema is provided, and an example input and output are also given.
About this solution: The solution is optimal because it uses the GROUP BY clause to group the rows by customer_id and then uses the SUM function to sum the revenue for each customer.
Write a SQL query that returns the total quantity of each product ordered by each customer.
About this solution: This solution is complete and solves the problem. The approach is straightforward and easy to follow.
This question asks for the 5th highest salary from the "Employees" table. The example input is a table with id, name, and salary columns, and the example output is a table with a salary column.
About this solution: The candidate's solution correctly finds the 5th highest salary from the "Employees" table. The solution uses the correct SQL syntax and demonstrates a good understanding of the problem.
The table has two columns, id and data. The query should return the data in ascending order of id.
About this solution: The candidate's solution does not demonstrate a level of completeness and does not solve the problem. The general approach is to select all data from the table, but this does not return the data in ascending order of id. To solve the problem, the candidate would need to add an 'ORDER BY' clause to the query.
Write a SQL query that returns the total quantity of each product ordered by each customer.
About this solution: The candidate's solution does not demonstrate a level of completeness and does not solve the problem. The candidate's approach is not clear.
This question asks for the 5th highest salary from the "Employees" table. The example input is a table with id, name, and salary columns, and the example output is a table with a salary column.
About this solution: The candidate's solution correctly finds the 5th highest salary from the "Employees" table. The solution uses the correct SQL syntax and demonstrates a good understanding of the problem.
The table has two columns, id and data. The query should return the data in ascending order of id.
About this solution: The candidate's solution correctly returns the data in the table in ascending order of id. The solution is complete and solves the problem. The approach is straightforward and easy to understand.