Connection pooling is a technique used to avoid the overhead making of new database connection every time. An application or server object requires access to a database. This technique of “pooling” connections is based on the fact that most applications only need a thread to have access JDBC connection when they are actively processing a transaction, which usually take only milliseconds to complete. While not processing a transaction, the connection would otherwise sit idle. Instead, connection pooling allows the idle connection to be used by some other thread to-do his useful work.
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