bparedStatement

PreparedStatement is an interface in Java Database Connectivity (JDBC) that represents a precompiled SQL statement. It is part of the `java.sql` package. PreparedStatement offers significant advantages over the simpler Statement interface, primarily in terms of performance and security.

One of the key benefits of PreparedStatement is its ability to prevent SQL injection vulnerabilities. This is achieved through the use of placeholders, typically represented by question marks (?), within the SQL query. These placeholders are substituted with actual values during the execution phase, rather than being directly concatenated into the SQL string. This separation of SQL code and data ensures that malicious input cannot alter the intended structure or execution of the query.

Furthermore, PreparedStatement can improve performance, especially when executing the same SQL statement multiple times with different parameters. The database precompiles the SQL statement once, meaning it parses, optimizes, and compiles the query plan. Subsequent executions then reuse this compiled plan, avoiding the overhead of parsing and compiling the statement repeatedly. This makes it particularly efficient for batch operations or loops that involve database updates or queries.

To use PreparedStatement, you first create a connection to the database. Then, you prepare the SQL statement using the connection's `prepareStatement()` method, providing the SQL query with placeholders. Next, you set the values for each placeholder using the appropriate `setXXX()` methods (e.g., `setString()`, `setInt()`, `setDate()`) based on the data type, specifying the placeholder index. Finally, you execute the prepared statement using methods like `executeQuery()` for SELECT statements or `executeUpdate()` for DML statements.