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To use connection pooling in plain JDBC with HikariCP, the main shift is: stop using DriverManager.getConnection(…) everywhere create one DataSource (the pool) at startup whenever you need a DB connection, call dataSource.getConnection() always close resources with try-with-resources (closing returns the connection to the pool, it does not kill the physical connection) 1) Create a pooled […]
Savepoints in JDBC provide fine-grained control over transactions by allowing you to roll back to a specific point within a transaction rather than undoing everything. This is particularly useful for handling optional operations or partial failures. Key Steps to Use Savepoints Disable Auto-commit: Savepoints only work within a manual transaction. Set a Savepoint: Use connection.setSavepoint() […]
Using transactions in JDBC is essential when you need to ensure that a group of SQL statements either all succeed or all fail together (maintaining Atomicity). By default, a JDBC Connection is in auto-commit mode, meaning every single SQL statement is treated as its own transaction and committed immediately. To manage transactions manually, follow these […]
To set the fetch size for large queries in Java using JDBC, you use the setFetchSize(int rows) method on a Statement or PreparedStatement object. This gives the JDBC driver a hint as to the number of rows that should be fetched from the database when more rows are needed. This is particularly useful for large […]
To use auto-generated keys in JDBC (like an AUTO_INCREMENT primary key), you need to follow a three-step process: notify the statement you want the keys, execute the update, and then retrieve them from a special ResultSet. Here is a practical example using PreparedStatement: 1. Prepare the Statement When creating your PreparedStatement, you must pass the […]
To batch insert data with JDBC, you typically use the addBatch() and executeBatch() methods. This is much more efficient than executing individual INSERT statements because it reduces the number of round-trips between your application and the database. The most common and secure way to do this is with a PreparedStatement. Batch Insert with PreparedStatement Using […]
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