As it name suggests, it just a pool of database CONNECTIONS. Since creating a new database connection in real-time is an expensive process and can potentially slow down the response time, many application maintains a pool of active database connection. When a request comes in they retrieve a connection from the pool, get the data from the database and then RETURN the connection back to pool so that it can be REUSED. This WAY, response time is improved in most of the Java web application. See here to setup a database connection pool in Tomcat using Spring framework.

As it name suggests, it just a pool of database connections. Since creating a new database connection in real-time is an expensive process and can potentially slow down the response time, many application maintains a pool of active database connection. When a request comes in they retrieve a connection from the pool, get the data from the database and then return the connection back to pool so that it can be reused. This way, response time is improved in most of the Java web application. See here to setup a database connection pool in Tomcat using Spring framework.