Connection Pool Examples
👉 Overview
👀 What ?
Connection pooling is a method used in programming to enhance the performance of executing commands on a database. In a connection pool, a predetermined number of connections are opened and kept alive so that they can be reused by multiple application threads.
🧐 Why ?
The need for connection pooling arises from the fact that opening and closing database connections are expensive processes in terms of system resources and time. By reusing existing connections, the application can significantly reduce the overhead and latency, leading to faster response times and increased system efficiency.
⛏️ How ?
To take advantage of connection pooling, developers need to use a programming library or middleware that supports it. When a new connection is requested, the middleware checks if there is an available connection in the pool. If not, it opens a new one. When the connection is no longer needed, it is returned to the pool instead of being closed, ready to be used by the next thread.
⏳ When ?
Connection pooling has been in practice since the early days of database-driven applications. Its usage has grown with the rise of web applications and services, where the efficient handling of numerous simultaneous database connections is critical.
⚙️ Technical Explanations
Under the hood, a connection pool works by maintaining a 'pool' of active database connections. This pool is usually implemented as a data structure such as a stack, queue, or set. When a connection is requested, the pool manager checks if there are any unused connections in the pool. If there are, it 'loans' one to the requester. If there aren't, it establishes a new connection to the database and adds it to the pool. Once the requester is done with the connection, it is 'returned' to the pool instead of being closed, making it available for the next requester.