How to solve java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/test

The error "java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/test" occurs when you try to connect MySQL database running on your localhost, listening on port 3306 port from Java program but either you don't have MySQL JDBC driver in your classpath or driver is not registered before calling the getConnection() method. Since JDBC API is part of JDK itself, when you write a Java program to connect any database like MySQL, SQL Server or Oracle, everything compiles fine, as you only use classes from JDK but at runtime, when the JDBC driver which is required to connect to database is not available, JDBC API either throws this error or "java.lang.ClassNotFoundException: com.mysql.jdbc.Driver".

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4 Ways to find Nth highest salary in SQL - Oracle, MSSQL and MySQL

One of the most common SQL interview questions is to find the Nth highest salary of employee, where N could be 2, 3, 4 or anything e.g. find the second highest salary in SQL. Sometimes this question is also twisted as to find the nth minimum salary in SQL. Since many Programmers only know the easy way to solve this problem e.g. by using SQL IN clause, which doesn't scale well, they struggle to write the SQL query when Interviewer keep asking about 4th highest, 5th highest and so on. In order to solve this problem effectively, you need to know about some key concepts like correlated subquery, window functions like ROW_NUMER(), RANK() and DENSE_RANK() etc. Once you know the generic logic to solve this problem, you can tackle all those variations by yourself.

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